Patrick Fulton (3 parts)

Beatriz Martinez-Rius (BMR): Today is November 21st of 2024, I am Beatriz Martinez-Rius onboard Chikyu, Expedition 405, and I am with Patrick Fulton, co-chief scientist. Thank you. So first, can you please say your name, your current affiliation and your position?

Patrick Fulton (PF): My name is Patrick Fulton. I’m from Cornell University in New York, United States. I’m an assistant professor in the Department of Earth and Atmospheric Sciences.

BMR: What are your research interests? In general, as well as how they connect with this expedition.

PF: I’m interested in hydrologic and thermal processes in fault zones. I like to know about heat, fluid flow, geomechanics, stress… Things like that. A lot of the things that I do for this project are related to trying to think about how fluids move around in the subsurface. One of the things that I’m very much interested in is the dynamic friction on faults. Even though I dabble with it, I’m not a true rock mechanics experimentalist. I try to get at it in a different way, through observations — maybe looking at frictional heat left over on faults, understand where the faults are weak… And then, also, how are fluids involved in weakening faults? Are fluids involved in weakening faults transiently by opening up and allowing them to flow through?

So that’s why I’m interested, particularly with this project, that is similar to things I’ve done in the past. I also use a lot of the things that I’ve learned from scientific ocean drilling and studying fluid flow and heat transport, particularly in faults and fractures. I use that same knowledge for geothermal energy now, as well.

BMR: Through which means do you study this? I mean, is it like geophysics? I don’t know how does this work — I only know that you are Mr. Sensors.

PF: (laughs) Yeah. So, a lot of what I do – or, in the most recent years, particularly after JFAST – is play a lot with sensors, temperature sensors, high resolution temperature… We put them into boreholes, to monitor temperature with depth over time. That has allowed us to see things. For JFAST, famously, we were able to see the frictional heat signature on the fault, across the fault that was left after the big earthquake. But we also see how fluids move around. So our sensors can measure to 1,000th of a degree Celsius in accuracy; they can resolve temperature even less than that. So, if you put them down, underground, and they’re just sitting there – it’s just like wind – you can sense and feel fluids moving around. So, we’ve seen that certain fractures that we’ve mapped, open up in response to earthquakes. You know, aftershocks of the main magnitude 9 earthquake. The earthquake happens, and they squirt out water for like a half a day. I’m being recorded, but I’m famously sometimes saying, we’ll say it goes like “pppffff” (all laugh) for like a half a day. That’s an interesting thing. So, essentially these faults are opening up and they’re transmitting fluids, and when they do that, they can transmit fluid pressures to other places, which might cause those other places to get weak or behave differently — maybe deform, maybe trigger an earthquake, those type of things. We’re seeing things at shallow depths, but those processes are probably happening at greater depths, as well.

BMR: I have a bunch of questions related to the sensors, and I have a bunch of questions related to how you arrived to your research subject. So instead of just going from one to the other and branching out, let’s start from the beginning. Where are you from?

PF: I’m from the state of Georgia in the United States. I grew up north of Atlanta, halfway between the city and halfway between the mountains.

BMR: Were any of your parents, close family, friends… Related to science or engineering?

PF: My dad is, I think he would call himself a computer engineer, in these days, a systems analyst. He worked for a railroad. So I was around some engineering-type of things. My uncle is a geologist.

BMR: Did they have any kind of influence in you choosing this pathway?

PF: Probably not. But, you know, I was always interested in science. When I was in second grade, out of a list of many things that you could do, like a science fair project on, I did mine on rocks and minerals, and I never looked back. Well, I did look back. I really liked it a lot, I really was interested in reading about all these things. I was fascinated by core samples, ironically. And so, that was very interesting to me.

There weren’t many programs for geology that I knew about in college and stuff. So, I kind of, got into Physics for a while. I really like physical processes, and such. But then, after taking like an insane modern physics exam, and it was insane, I remember walking across campus and seeing that Earth and Atmospheric Sciences building and said, “Oh, those lucky bastards get to go outside”. So, I changed my major, and I called my parents, and I said, “Oh, it’s a big deal and everything. I hope you don’t mind. I decided to change my major from physics to earth and atmospheric sciences”. And they said, “Oh, well, we always knew you were going to be a geologist”. And I was like, “Well, who knows?”. That said, I don’t consider myself a real geologist. I don’t know, I guess I’m not as good of a geologist as some of these other folks are. But I do think a lot in terms of physics, maybe more hydrology, thermal geophysics, geomechanics… Those type of things.

BMR: When you say that you were fascinated by cores, was it ocean drilling cores?

PF: It was not ocean drilling cores. I didn’t even know about ocean drilling. But I remember going to museums, and seeing core samples that were probably from geotechnical core samples or other things, and I found it fascinating. I remember seeing, every once in a while, a well drilling rig driving down the road, and being totally fascinated and being like, “That is so cool”. It is still pretty cool. Yeah.

BMR: So it was actually the idea of going down into the Earth, and getting something from there.

PF: Absolutely, yeah. And then that you could tell something about what was down there, and you can interpret a lot of different things. That’s pretty cool, to me.

BMR: How from that early understanding of physics, to then moving to earth sciences, how did you get into hydrogeology?

PF: I also like to spend a lot of time outdoors in the mountains and other things. Especially if you spend a lot of time out there, essentially, you start looking for water because you’ve spent too much time (laughs). You get dehydrated. So, you’re looking for springs and other things, and just running water over things. So, I really was interested in hydrology. I saw that people that were doing hydrology actually got to go outside. They were using wells to study things. So, I looked and tried to do research with someone doing groundwater hydrology in my undergrad. Eventually I was able to do that. That was my first well drilling. Really, it was well-digging. It was very shallow wells and then, eventually, maybe two or three meters depth. And sometimes we created systems, vibro-coring systems – that was my undergraduate project. It was to design and build a vibro-coring system through mud; like our piston cores, to vibrate a piece of irrigation pipe down into the ground, and then through the mud, use a tripod and a winch, and suck it out. Then, we had a core sample, and we had an open hole that we could put a well into. So that was my first work, my first drilling, my first well.

Hydrology is really fun and interesting, but it’s also been around for a long time. Don’t tell anybody – but I really think that hydrology, regular hydrology, is a little boring. I didn’t want to do, like, contaminant transport. Of course it’s important, and I’m glad that people do it, but I didn’t want to spend my life cleaning up gas stations in New Jersey or something (all laugh). So, I was also very much interested in faults, and structures, and the stresses on faults. I was able to go out to New Mexico and learn geophysics, and see all the things that you saw as like a kindergarten, like volcanoes on the landscape and everything. It’s real. And so, I would try to see and ask around, “is there any way I can combine hydrology with faults?”. And there were a few people doing that. Because hydrology can influence faults and fault behavior in earthquakes.

So, a combination of that and a number of things led me to my PhD advisor, who was very much involved in IODP. My undergraduate advisor was involved in IODP, or in ocean drilling. But I did not do ocean drilling at all until much, much later.

My PhD project was on the San Andreas fault, and questions about, what are the forces acting on the fault? What is the frictional resistance of it? How slippery is it? And so, it was a question that had been out there for a long time, and one way that you can get to that — seismology is great. My wife is a seismologist. It can tell you a lot of things maybe about how much stress changed during an earthquake, but it can’t tell you the absolute magnitude of stresses on faults. But one way that you could get to the shear resistance on faults is by measuring how much frictional heat is generated by them. So, on the San Andreas fault, people looked for the frictional heat that was generated by earthquakes over, and accumulated around the fault, after millions of years of shearing. You would think that the heat flow, essentially kind of the temperature gradient around the fault, would be increased across many tens of kilometers around the fault.

So, people drilled wells and they had to go deep down to get away from the climate and daily seasonal effects of temperature. And they would measure the temperature gradient, measure some properties of the rocks, and get the heat flow, how much heat is coming out. And they would expect like this big increase across fault – and they didn’t see it. So, is that because the fault was really strong? Or was really weak, really slippery? Or was it because it still had these levels of friction that laboratory experiments suggest they might have, but all the heat was just washed away? So, I spent a lot of time working on that problem.

BMR: You are talking about heat flow… But I’m not sure I understood the relation between hydrogeology and heat flow.

PF: Oh, that’s right, because it has nothing to do it! (all laugh). Well, one of the things is the question of whether groundwater flow washed it away. That’s where I brought in some hydrology. So, is just the hydrology – just, you know, rain falls on the hills, it kind of goes down into the valleys and stuff like that; but also underground, too, groundwater accumulates up there, and as it recharges into the ground, eventually it flows into other places. Is that process enough? Even if the rocks are super permeable – which we don’t know, they probably aren’t – is it possible to just wash away the heat? So, I spent a lot of time analyzing the heat flow data, modeling that process, as a modeler. I didn’t even go out to the field except for just visit friends that were doing other things out there, to help them. But mainly just a modeler, analyzing data that was collected 20, 30 years previous.

But then, I answered that question; but then I also did a lot of modeling of testing hypotheses. People said, “Well, we think it might actually be very weak. Why is it weak? Is it because there’s some magic minerals in there, that are really slippery? Or is it high fluid pressures that are in the fault, essentially opening it up?”. There were a bunch of ideas out there. And I ran a bunch of models trying to test with reasonable values of different things, are those realistic, or reasonable, or not? So, that’s hydrologic processes related to faults, and weakening, some things related to heat flow, heat transport…

BMR: Which years was this, more or less? And I’m asking because I just want to have an idea of, when you say modeling, the state of technology at that point. I’m not suggesting you are a pre-computer person… (all laugh)

PF: Well, we used an abacus and mud… (all laugh). This was around between, 2002 to 2008. But yeah, it was before I started using a Mac. So I used Windows, the computer language or the computer program was written in Fortran and, yeah, it’s pretty terrible.

BMR: Before I forget, can you tell me the names of your supervisors?

PF: Sure. It’s going to be common names. Demian Saffer was my PhD advisor. He’s been very famously involved in a lot of Chikyu expeditions. But then, my undergraduate advisor is Carolyn Ruppel. She’s a hydrologist. And I think she really started to get into drilling and things on land from her experiences with, at the time, it was ODP drilling for gas hydrates.

BMR: So how all this, understanding of the behavior of the San Andreas fault transformed into underwater studies?

PF: Great. So this is really where the story of JFAST comes about. The last year of my PhD, at AGU 2007, getting into my last year of my PhD, a colleague of ours, Emily Brodsky, came up to me and Demian. We were standing in the poster hall. And she came up to Demian and said, “Demian, have you ever thought about how water may, or groundwater may, wash away the heat after a single earthquake?”. And he said, “No, I’ve never thought about that. But Patrick has”, because it was very similar to the kind of projects that I was working on, understanding whether groundwater flow could wash away heat for millions of years of heating along a fault. But what happens in a single earthquake? So, I had started to kind of do some models on my own, just kind of thinking about what happens in an earthquake and how does water move around, maybe move heat around, and such. So, I had started models like that. So, she said, “Interesting. Why don’t we all grab a beer or something to drink later in the week?”. We went and she says, “I’m very much interested in this question of what are the forces acting on a fault? What are the resistance of it? What is the dynamic friction on faults during an earthquake?”.

She knew that you can’t really get from seismology. The way to do it, is to drill into a fault after an earthquake. And she had been trying to kind of get a workshop together, try to think about this. It had been tried a few times before, unsuccessfully. She really wanted to move this forward so we can get to this answer. But even just to get like a workshop proposal, people said, “it’s impossible. Maybe it might be possible, but logistically, practically, it’s impossible.” You have to get there – like, earthquake happens, creates a lot of heat on a fault. To see that single… heat quickly diffuses into the surroundings. So it might be like a thousand degrees on the fault in the millimeter to centimeter thick slip zone but then, within a second, it’s half the temperature and it’s spaced out a little bit longer.

A year later, it could be less than a degree, and spread over a long distance. So, to be able to see this, you have to drill into a fault zone really soon – like, within a year of the earthquake. And you have to go to some place where there’s a lot of displacement – more heat. So the idea is, the amount of heat per unit area that is generated by frictional heating is related to two things: it’s the product of the average shear stress, which we’re trying to get to, during slip. And the amount of displacement there was. So, if you have more displacement, bigger slip, you can perhaps see a bigger signal. You probably also want to go to depth, so it’s not affected by shallow groundwater flow. And also, as you go deeper, just the normal stresses, the background stresses, acting on things increases.

So, the idea was that you need to go there about one year after the earthquake, drill through about a kilometer deep, and you need to go someplace with a big amount of slip. Most people said, “it’s not even worth thinking about this. It’s impossible. You can’t do it. And then even if you could try to go down there, you get your sensor, or you try to do a temperature survey across it, how are you going to know if that’s really – it’s a small thing – how are you going to know that’s really this frictional heat, or something else? Or, it’s just going to be washed away by groundwater flow?”

So, they weren’t even able to fund a workshop. They’re like, “Impossible, don’t bother”. She asked me if I was interested in this, and I said, “Yeah, sounds great”. So, I immediately got to running models to think about how would you do this experiment? Would it get washed away by groundwater flow? If so, was there something that you could see in the observations that could tell you that that’s what’s going on? So, I spent a lot of time working on that.

I graduate, and actually graduated with my PhD, and I kind of worked on that problem on the side for a while. But we eventually got the workshop. We had a big conference workshop in Japan, to think about, if there’s a big earthquake – this is in 2009 – if there is a big earthquake, we should respond as a community. There’s so much that we can learn from that. And perhaps, we can get to this question that we all kind of want to know: what are the forces acting on faults? What is the brakes that control whether they get big, or whether they stop, or they slip all the way to the trenches? So, we came up with this thing, a lot of models and a strategy of things. I came up with ideas of how you would do this – one was that, again, big slip, kilometer deep borehole, one year after the earthquake. So, we tried to think that through. Also, if you were going to do it, instead of just running one temperature survey, you probably want to do many surveys where you want to keep sensors there. So you could see how it changes over time, whether the temperature is continuing to diffuse, or whether you see signals of advective fluid flow. So, that was going on.

We generally thought – or at least, I thought – that if there was a big earthquake, every once in a while, we have a big earthquake, we’re like, “This the one! Should we try to get all the forces together, get a drill rig, and go drill into it?”, I thought that the big earthquake was going to be on land. Because generally in subduction zones, the shallow part doesn’t slip.

BMR: In subduction zones the shallow… can you say that again?

PF: Yeah. In subduction zones, the shallow part of the fault does not slip in an earthquake. It doesn’t do anything. It just sits there. So usually, our model – now probably incorrect – our model was that an earthquake starts big, like in a megathrust subduction zone, like Sumatra, starts down deep, 30km deep; has its hypocenter down there, it has a lot of slip and then, if you mapping the amount of slip, kind of dies out like a bull’s eye. And then it kind of gets to maybe shallow depth, maybe a kilometer and then it dies out. It just kind of fizzles out in all the sediment and other things up in the shallow part. So, if we were going to go to some place with a lot of slip, you’re going to have to drill like five kilometers or something like that. So, I just presumed that on land there are some places, like on thrust faults, where the rocks are really rocks now, and sometimes they rupture to the surface. And actually, in 2008, there was an earthquake. We started this in 2007, thinking about this, talking to colleagues… And in May of 2008, there was magnitude 8.3 earthquake, probably the magnitude may be wrong, in China. The Wenchuan earthquake, on the Longmenshan Fault, on the edge of the Tibetan plateau. And so there was an effort by the Chinese government to drill some holes across the fault, and we consulted with them, or they consulted with us, and tried to think about measuring frictional heat. In the end, I was involved a bit with that and it was complicated. The groundwater washed away the heat, probably, and maybe also it might have been many faults that ruptured. It’s hard to figure out which fault was the one that slipped.

BMR: Several things surprised me. The first one is that you started to put this together with Japanese colleagues.

PF: Yeah.

BMR: It kind of makes sense because the community of people in Japan studying earthquakes is pretty big, but it kind of surprises me, because you were in the US thinking about doing this study and immediately you turned to the Japanese. And the other thing is that, if I understood correctly, drilling into the ocean was always one of the options for these studies…?

PF: Maybe, but we don’t really think so.

BMR: At that point, you didn’t think of yourself as a person who would go into a ship because there will be this mass of water here that you wanted to avoid.

PF: Well, actually in the meantime – so I graduate in my PhD, I go to a postdoc in Oregon. And I had some funding, but not a lot of funding. Sometimes it was a little, the combination was that I had a little bit of freedom to do what I wanted on top of the regular project I had. But it also meant that sometimes I didn’t have funding, so I had to do other crazy projects. So, when I was there in Oregon, I said, “Oh!”, it was the kind of place, an oceanographic kind of institute. They sometimes had people that would go out to sea. And so I said, “Oh, I want to go out to sea”. So, on the email list server it said, “we’re looking for someone to go out to sea for one day”. To help collect some stuff. I volunteered and went out, and was incredibly seasick. And everyone was seasick except for the captain, first mate, the ship crew. It was such a small ship. That was all that they had. And, then they said, “oh, thanks for volunteering. We had to ask for a volunteer because the PI, the principal investigator, can’t go out anymore. She gets too sick”. (all laugh)

So that was not the best introduction to ship going life. But later, from that postdoc too, all of my colleagues, mentors and other things, people that I looked up to, including Demian Safer, Peter Flemings, and others, they suggested, “You should get involved in IODP, in ocean drilling. It’s just such a great community. It also encourages leadership development in other things. You will have, opportunities to kind of grow and learn and do a lot of things”. So, I got myself onto a ship. I got myself onto an IODP expedition. It didn’t include any bribery or anything. I just had to do two months of physical properties’ analysis. That’s how it always works, right? So, it didn’t involve any faults; it was on IODP Expedition 330, Louisville seamounts off coast of New Zealand – far off coast New Zealand. And pretty much everyone on board was a p-mag [paleomagnetic] specialist or petrologist. And then, there were a few other people, but largely I hung out with the microbiologist. We talked a bit about hydrology. Then, I had experience now with IODP and in drilling; I learned a lot from that.

And so, all this comes then to March 11th, 2011. Magnitude 9 earthquake. The Tohoku-Oki earthquake. We were all shell shocked by it, and amazed by it, thinking of our colleagues and friends in Japan, and worrying about them. But a few weeks after it, Emily [Brodsky] sent me an email and said, “Hey, this might be our earthquake. Can you run your models for 50m of slip on a thrust fault?”, “at this kind of angle?”, and things like that. And I thought she had a typo. So, I ran the models for five meters of slip. I was like, “if there was five meters of slip in a shallow part of the fault, if there was five meters of slip all the way to the seafloor, that would have been huge news”. And it was huge news. In Sumatra, it was a big deal that people thought that maybe the slip got close to the seafloor. It was kind of big news. So, five meters of slip on the seafloor would have been big deal. And so, I ran it, and she’s like, “I would have thought the signal would be bigger. [Are] you sure you ran it for 50?” I was like, “Emily, that’s not… That’s not realistic. Do you really have constraints?”; like, “How do you think that you know in just a few weeks after the earthquake that was 50 meters all the way to the seafloor?”. And she showed me some of the results that Shuichi Kodaira and his team, Fujiwara and others, had done, or they had done high-resolution bathymetry surveys within a few weeks after the earthquake, even though many people still don’t have power, they went out, and re-surveyed the place. This is why we came to Japan ahead of time. The most geophysical characterized place, particularly for earthquakes and geohazards. So even though there was a lot of attention to Nankai in the south, this whole part to the north has been surveyed and been looked at. And they did expect a big earthquake, here. So, they went back out and they re-surveyed. And they could see that there was a shift in bathymetry, and the only way that you could explain it, is if the whole shallow part of the fault all moved all together at once 50-60m, all the way to the east. Remarkable. Yeah.

So, we ran those models, and we started to think about, “well, could we go…?”. Well, everyone thought too, this is a huge, gigantic earthquake. It really took us by – well, not by surprise – people expected, we all expected, a big earthquake here; but the magnitude of it was a lot bigger than we expected. Fukushima has a nine meter tall tsunami wall, but when the tsunami is 13 meters… That doesn’t help as much. So, there was a lot of thought of that, “Did we get it wrong?”. It was completely different from our model of big amount of slip down deep, then it kind of fizzles out. No one really expected this. “How do we get it wrong?”. But also, with such a big devastation, “Is there anything that we can do as geoscientists?”. We can study faults and all these things, but when it comes down to how they affect people… The earthquake happened, they’re going to continue to happen, but can we learn anything from it that allows us to know better of the hazards in other places? To be more prepared in other places? Is there anything we can learn from this?

So, I think there was a general movement of a lot of people to drop what they were doing, and see if it was possible to learn as much, in a short amount of time. So, we started looking around and saying, “Hey, is it possible to drill across the fault? Can we learn anything from drilling, getting in there where it’s actually happening?” And so, we particularly – Emily [Brodsky] kind of led the charge, talked to my former advisor, Demian Saffer, Harold Tobin, others involved with Chikyu drilling, with Nankai to the south, and said, “Japan has the best, most highly equipped scientific ocean drilling ship in the world. Chikyu. Is there anything we can do with it?”. Also, we have this idea that if we really want to know this one thing, there’s a lot of things we can learn. But there’s one thing about the dynamic forces acting on it. If we can figure that out, it may answer for us why… Or give us better understanding of why did the shallow part slip so much? Why did it jump 50m? Is it because the shallow part was really strong? And so, the down-going plate is going down and it gets stuck, and just builds up a lot of elastic energy here – it’s like a rubber band is ready to go? Or is it really weak, and it has like, no brakes? The rupture comes through, no brakes. It just kind of like hydroplanes. So, you know, that answer of why did this happen? Why was it so much bigger? Why? When the shallow part slips that much, the area of slip gets a lot bigger, the magnitude of the earthquake gets bigger. But also, when the seafloor jumps 50m, you’re going to displace a lot of water. You’re going to create a much bigger tsunami than you ever expected. So maybe, we can understand something if we could get down there.

We started talking with JAMSTEC, started talking with Chikyu, started talking with IODP, and said, “Is this impossible?” (sighs). “Maybe that’s a thing… Not impossible, but…”; or, I guess the answer was never “no”. It was like, “Very difficult and other things”, essentially what we wanted to do was just at the edge of what’s possible.

BMR: Why at the edge? Do you mean in terms of money, in terms of depth, in terms of fast organization…?

PF: All of the above. The main thing was, just before we get too crazy into this and to say, “Oh, let’s try to put this together!”, what is the water depth? First thing, if we want to cross the fault, somewhere around one kilometer underground so that it has enough stress that we can actually see a signal, we wanted to go someplace where we have good constraint on the displacement. This place is very close to where that repeat bathymetry line is. So, we could say, “Oh, for sure, somewhere around 50m a slip”. Okay, so now look at the cross section. Luckily with IODP you need to have site surveys and all these things. Japan has surveyed this place so many times. All these cross sections, of seismic surveys. “Let’s look at the seismic survey.” “Okay, where can we get to one kilometer to the fault? Do we know where the fault is? Is there a place where we can think that we know where the fault is Within a kilometer?”. “Okay, it’s around here”. “What’s the water depth now?” That’s where we’re at seven kilometers. So, seven kilometers. Well, that’s about… No one had ever really tried to drill at seven kilometers, except for a couple of really old DSDP legs in the Marianas where they took, like a one meter core and a three meter core. But here we want to go, like 850m or so.

First, we want to go down logging while drilling. Where is this fault? Can we find the fault? Where is it? If so, the idea, though, is that the main thing – well, for me – the main thing that really kind of made us want to get there soon, is that the heat is diffusing away. We got to get there within about a year after the earthquake. If we’re going to really kind of have any chance of seeing a signal before it diffuses away forever. And then we have to – I hope in my lifetime there’s not another magnitude nine earthquake. But, you know, this is our opportunity to do it. So, we have to get there soon. So that’s a whole thing. But first, physically, mechanically, other things, can Chikyu go to seven kilometers? Yes. Just at its limit, seven kilometers plus maybe a kilometer of drill pipe. The derrick can hold that. If they get some other types of pipe that are strong enough, and other things, may be able to be done. Maybe. On the edge. Then, we want to drill across the fault. So, compared to one meter, three meters in Marianas, we want to drill down across fault. Find the fault. We then want to go down. We want to actually confirm that through the fault. We want to core through it, take a biopsy of it, see what it is. Like, some magic clay or some other minerals in there? But then, we also want to build an observatory, drill a hole. And when you drill a hole, you kind of disturb the temperature for a little while. You circulate cold ocean water. So, we can’t just measure the temperature right after we drill it. We have to wait some time later. It’s not possible to just measure the temperature right after we drill it. We have to wait some time for it to recalibrate with the formation. So, you’re going to have to go back and do a thing. And our whole bit was that, to do all this analysis, really know whether it’s heat or fluid flow… and, if you see an anomaly, you’ve got to measure it multiple times to kind of see how it changes over time. So, is Chikyu going to come back and just do a survey every once in a while? Probably unlikely. Instead, we would want to put sensors down there, measure over time, and monitor over time. So that comes the design of it later on. But, that meant that we need to drill a hole, and then we need to put a whole observatory cased inside there, with temperature sensors later on. That’s a lot different than taking a little one meter sample.

So that’s what’s at the end the “on the edge”. To do that, you drill a hole, you have to go back and you have to thread the needle and go back in. You have to be able to see down there. Also, we want to then get our data back. Wouldn’t that be nice? So, to get the data back, we need a ROV or something, to come back, to be able to pull the sensors out, or to collect the data. Ah, now we’re on the edge of things. Only one submarine, ROV, or other thing that can really manipulate and do the things that we need to do, only one is capable at that water depth: Kaiko. Kaiko, at the time called Kaiko II 7000, because it’s maximum water depth was 7000m below the seafloor. Our water depth at our observatory in J-FAST: 6995m.

BMR: (laughs) Always at the limit.

PF: (laughs) Yes, just pushing the limit.  And that’s an interesting part of the story with J-TRACK, which is a different story. Kaiko can no longer go to 7000m. No ROV, to my knowledge, can go to those water depths. At least one that could do… pull the sensors and those type of things. So, we have to push the technology, come up with creative ideas to solve that problem. So, we have to do this. All these things, just at the limits of Chikyu.

Now, the other bit: the organizational bit, the funding bit, and other things. I think Japan was trying to do a lot of things, recovering and do many, many things. But, I think, a lot of people realized that we should do as much as we can. This is an important thing, to get as much science good from a terrible disaster. So, a lot of other people, though in the IODP community, including these leaders from NanTroSEIZE said, “We’re familiar with the system, we’re familiar with Chikyu, what’s possible, what it could do, building observatories… Everything”. A lot of people dropped what they were doing to try to make this move forward on many different levels.

Part one was IODP to say – you know, usually when you write an IODP proposal, usually it goes through the system and it could take 5, 10 [years]… This one [JTRACK] took like 12 years to go through, and before write a proposal, and get through. Is there any way – no one had ever done, there’s no program or way of thinking on rapid response drilling. But we had a little bit, this framework from this workshop we had in 2009, of what are the things you need to put in place. And we had these papers on how you could do this experiment. And we had thought through all the important things that you need to think about how to do it, right?

So, there was kind of a framework there. We wrote a proposal, and IODP went through their regular science program, and they had these committees that reviewed it, safety evaluation panels, and other things. And got it through the system. I think a lot of people really thought the science was good, and that it was possible to try and move it forward.

BMR: Do you think there was this community feeling that this was like a [justified] exception in the system of IODP?

PF: Well, I don’t think it was an exception. You know, I think that it went through the regular science things.

BMR: But it went superfast.

PF: It went superfast. And so they did put the exception of the rapid review of these things.

BMR: So instead of taking six years…

PF: Yes. I think most people recognized the importance, and the importance of doing it quickly for many reasons. One, for the experiment, but – I think it was an important experiment. It was very successful. But I think also people want to do something now after a disaster. It would be one thing to say, “Oh, we’re going to go and study it 12 years later”. We are doing it [JTRACK] 12 years later. But, when the public and other things are frightened, and rightfully so, and saying, “How did this happen?”. This is the opportunity to actually go and show the importance of science, and show what science can do. So, I think that that was part of it, too.

BMR: You have been talking about the temperature, introducing sensors and recording the changes in temperature, and this has to be done pretty fast. But did everyone see the importance of temperature, or was it more seen as a secondary goal?

PF: Well, there was secondarygoals as well. I think much of the urgency was related to the temperature part. But there we other goals of going there as well – the observatory was very risky, had very high potential to not work. One, if you go down there and you measure it – well, I think many people, many big experts said, again, just like we when we started thinking about it, “Impossible. Even if you could do it, it’s going to be complicated. The fault might not be in one place. It’ll be complicated. And another thing is groundwater will wash it away, or other things”. But then, just the installation of an observatory, again, not much had been done at these water depths before. You know, being able to reenter a hole in this water depth had never been done before. So, just to be able to get sensors into the ground would be an amazing feat. Probably unlikely. So, I think there were certainly other objectives to go here; mainly, to see what is in the plate boundary fault. Is there anything there that is special, that made it so that this subduction zone and this earthquake had this huge amount of slip? Is it something different to Cascadia? Is it something different from Nankai? Should we expect this huge amount of slip in other places? I think people certainly wanted to know what is down there.

BMR: So then, what happened then?

PF: The next part was that, it moved forward and in that, we had an objective to try to get there a year after the earthquake. We had to go through all the IODP process and all those things, but in parallel, “This thing might go; we might be able to do that”. We have to figure out what are our priorities. We want to measure LWD [Logging While Drilling] so we can find the fault. And so, we have also raised some funds to pay for that. We also wanted to build an observatory. So, we have to raise some funds. Those things are usually kind of separate outside of a regular IODP proposal, so we had to find some way to try to fund that. But then, we have to design it, too.

BMR: One thing. At this point, at which stage of your career were you? You were probably a quite early career scientist, but at the same time you were involved in the organizational part of things.

PF: Yeah. This is the lucky and unlucky part of it. The lucky part was that, right before this earthquake, I had moved from Oregon where I was doing a postdoc. I got a special fellowship at UTIG, University of Texas Institute for Geophysics. I had a fellowship there, too, that paid me two years to essentially do what I wanted. So, that was very lucky for me. I was doing some things on earthquake energy budget, and working with my friends on rock mechanics experiments, and other things. But I dropped everything, and I was doing some of this stuff on the side. And so, I dropped what I was doing and just worked on running models and thinking about designing the observatory. But I had the freedom to do that.

But also, the unlucky part, maybe the risky part with this whole project, high risk, high reward. Early in my career, I have a few papers on the San Andreas and things like that. I’m putting all my investment in this experiment. This experiment that I might not even get the sensors in the ground. Then, I have to wait nine months, a year, or something like that to get any data back. I might not get any of the data back. Maybe the fault moves and grab the sensors. I can’t get them out. Or, they come out and they show nothing. You can’t really write a paper. Or you could, but people aren’t very much interested in, “We lost the sensors”, or, “we didn’t do it”, or – I do have a paper on, “We didn’t see the signal” from the China stuff. But yeah, you’re not familiar with that one (all laugh). So, it was a bit of a risk, but… I took a chance. Because it sure seemed a lot more fun than cleaning up gas stations in New Jersey (all laugh). But, you know, there were opportunities, there were other things I could do if it didn’t work out. That’s a little bit of a privilege. I don’t think everyone would take that risk.

BMR: That’s really cool. And I should say — I keep thinking all the time, I have to say, on how lucky were you of, just after thinking about this in a theoretical way, to have a magnitude 9 earthquake. I mean, it could have happen this year, or in ten years from now. It could have happened well advanced in your career!

PF: Yeah. And now I’m tired. And now I can only do co-chief jobs. (all laugh)

BMR: So, you were organizing and thinking about developing this observatory model.

PF: Yeah.

BMR: Where you working with someone on this? Was someone mentoring you?

PF: Yeah, well, that was the thing. I had a mentor and someone who is really pushing this project beyond what I could do, had connections or didn’t have connections, but would just push it forward. That’s Emily Brodsky. Emily Brodsky is the one that really pushed JFAST. She’s the one who had the original idea. You know, other people had done this idea, but she’s the one that pushed it forward. When people said, “Don’t bother, we won’t even find a workshop. It’s impossible”. She pushed it forward. She found people to help her out. She found me and said, “Can you run some models?”, “try this”, “What would you do, think about this problem?”. She pushed it forward. When it came to talking to Japan, and thinking about whether this would happen, and the answer was not no… So, she pushed it forward. Maybe sometimes the answer was no, but she pushed it forward.

So, I think a lot of it comes from Emily. She was my mentor, and pushed it through. I also then, with that, it gave me the freedom of trying to think about all these different things. It probably gave me the freedom of thinking about how do I design an observatory. We all each had a little bit of things that we could concentrate on. People here – [Shuichi] Kodaira-san and others in Japan, how do we get this funded? How do we get this moved? And such. Moving through the system, a lot of people in IODP did that.  How do we find the funding for LWD, the sensors…? That one was a tricky one. And, luckily, IODP-MI (Management International) – it’s kind of an organizational group that had a pool of money left over from things, had a little bit of money left, and they paid for LWD and some of the sensors.

BMR: Oh yes, it was before 2013, so this was at the end of the Integrated Ocean Drilling Program.

PF: J-FAST was the last expedition, I think, last expedition of the other IODP.

BMR: It might not have happened later, because the funding routes were different.

PF: Oh, certainly. And I think that that’s why we could use some funding from them, was that IODP-MI was going to dissolve, but they had this little extra pool of money. So, we could use that for LWD and for 55 temperature sensors. We talked to a lot of government agencies. But, they said, “Too high risk. Too high risk. No way. Again, it’s impossible. There’s no way that’s going to work. We don’t even believe that you’re actually going to get out on the ship. Don’t even talk to us until you have, like, a real signed contract that the ship is going to go out”. And to my knowledge, I could be wrong with this, but I think that that signed contract didn’t really get signed until we were in port and already kind of boarding.

So, we put this all together, and tried to think about how do you how do you do this. And so that’s where I came to talk to a lot of people. Keir Becker, and Andy Fisher, other IODP wizards… That had a lot of experience with temperature. They study hydrology in oceanic crust, and they have put out temperature sensors into things to monitor temperature over time. They have ones where you have one data logger and then like a string underneath, a bunch of sensors, and they have maybe like 10, 12, often times 6 sensors. And they tell them the temperature for their things. It’s really interesting. Sometimes, you might want to move them around. And so, they have other systems where they just have these high resolution sensors, called Miniature Temperature Loggers, that were metal, and you would strap on or tie them onto a rope, and you’d hang them into a well, and then later you can pull them out, and they record the data. Those were really useful for them to understand a lot of things about hydrology in the ocean crust.

So I said, this is a way that you could potentially measure the temperature across the fault. One of the things that we learned is that we don’t know exactly where the fault is. We’re going to learn from the LWD. We can’t or we did actually build a separate system that has a cable with some sensors on it. One data logger, maybe the ROV can just download the data. We can leave it down there. But you need to know where – you’re limited by the number of sensors. If we’re going to measure the temperature anomaly across the fault, we really want to know the peak of it, so we get the magnitude of it right. You got to know where the fault is, and you got to have a pretty close spacing of a lot of sensors across there. Maybe the fault is a little deeper in this hole than that hole. You’ve got to have a lot of close sensors. So, in the end, in terms of money, we could raise enough for a number of sensors that we could do that. 55 sensors. Most of them concentrated around this plate boundary fault and damage zone area that we identified in logging, and in the core, around 820m below the seafloor. Spacing about a meter and a half across from them. And then kind of spaced out in other places. Maybe that’s not the where the fault slipped. There is another fault – or we thought there was another fault, might not be a fault – there’s another fault that was shallower. We were like, “Wow, that’s really cool. And what if that’s the one that slipped? Maybe the plate boundary didn’t slip. Maybe this one slipped. So, we put some over there, too. So, you need a lot of sensors.

BMR: Because when you’re saying that you used LWD, it means that once you were out with Chikyu, you planned to do LWD and then figure out where the section was. So it was a sort of… a process that developed at the same time the expedition developed. So you could not put together a proposal saying, we set the sensors here…

PF: Well, we had something like that. Essentially, we could tell from logging or from the seismic, the down-going plate is here, the basalt is here, chert layer is maybe this reflector… Generally, around 800m below sea seafloor we think we’re going to cross the plate boundary fault. So generally, around there, this is how we would distribute the sensors. And so, compared to our models of hydrothermal circulation or geothermal, with fluid flow advection moving around, disturbing things like that… Even with them, we think we could still interpret the signal. So, all those things went into the proposal, all those models. That would have been very, very difficult to do from scratch. We built them, but we had those models kind of built up. We could adapt them for this earthquake. We could compare to the papers we already had out about this process of how you would do this experiment. So, we could point to that.

But yeah, we didn’t really know. We had to kind of adjust a little bit on the fly. That also meant individual sensors where you can move them around was really useful. So I learned a lot from them. I continue to learn a lot from them, including like how to tie it, what knots to tie, how do you splice little loops into the rope, how do you make it the right length… For other projects, too, I’ve done this. That’s been very useful.

BMR: Just to recap, you haven’t worked before with any kind of CORK observatory.

PF: (nods)

BMR: Okay. You learned it from this people who had been installing some of the ODP, IODP observatories.

PF: Yeah, yeah.

BMR: I keep thinking on how do you develop an observatory? I keep having this question for essentially any instrument that is used here, in scientific ocean drilling. I know many tools are sent to this company in Singapore who designs the instruments for Chikyu. But it’s not only engineering, is also the scientists who will work with those tools, who interact.

PF: Yeah. So, for in comparison, after I learned how to do an observatory, or after I had experience doing it with JFAST, I worked with colleagues and we built two observatories in the Hikarangi margin [New Zealand], to do subseafloor observatory studies for slow slip earthquakes. It took us five years of design work, for those observatories.

BMR: Design work means that you are in your office, in the Geophysics department, and you send it to a technician, and they say if this can be done…

PF: I work in a college of engineering, but I’m not a real engineer. Just like I’m not a real geologist. But we would come up with the science, and we would go to College Station. And we would talk to the engineers, IODP engineers. They have a lot of experience building these things. Even with JFAST. So, how do you design this thing? You don’t design it from scratch. You build on what you’ve learned and done before. So, all of our crazy ideas, including this really complex one in Hikurangi, took five years, with the combination of many decades of experience. Keep it simple. We have less than one year. We’re still building it. And we’re going to go out to sea. So now it’s like, nine months, maybe six months, before we’re going to go out to sea. We can’t do something crazier. We’ve got to do it simple. So, the idea is essentially, for JFAST, was very similar to the simplest and most basic observatories, or just holes in the ground where they put casing in from ODP days. And so, we built and we had some other systems where we can have two observatories, one with kind of pressure and other things. But in the end, what was installed was the most simple, basic one. Essentially casing into a hole, a little ball-valve at the bottom so you can put it in, circulate water, no water can go inside of the casing – they don’t even call it casing. It’s so small, it’s 4.5 inch diameter. They call it tubing – so tubing, no cement on the outside – it’s too deep for any of that stuff. Just that into the hole with a wellhead. And a rope. A rope with a weight on the bottom. And we just, tie, wrap, our sensors around them. Wrap them with rubber so that they can go in and out really smoothly. They won’t kind of get caught and stuff.

So, rope, kind of like a static climbing rope, a weight on the bottom, a bunch of sensors on them positioned at different depths. And then, at the top was just like a hanger that everything hung underneath, kind of sat kind of like a CORK or something that sits on the top, plugs the top of the hole, and then had this little ring on the top, and you could see it. And then later on with an ROV, you can just hook onto it and pull it out. Simple.

Also, with individual sensors – several kilometers water depth, another kilometer underground, pretty much, if they’re rated to ten… Well, one, we needed sensors that could withstand those depths. These ones that had been used in oceanography; other people had used, have super high resolution. If we’re going to try to measure something really small, like a tenth of degree or something like that, we need very fine resolution. Most temperature sensors or other things, or even fiber optics, have like temperature resolution of 0.1, 0.2 degrees. That’s like the size of our signal. We need super sensitive sensors. So, these things luckily had been used in IODP and in oceanographic things before. And then, we had to find ones that were encased in titanium to deal with the huge water depths down there, too. So, they didn’t just implode, but if they did implode, or they got leaks, or something like that, water got into them, having each one have their own data logger, meant that, well, if that one screws up, we have them on the other ones.

BMR: Did you do any pressure test?

PF: We did. We built another temperature system, redundancy.

BMR: So, you were not eating or sleeping during, like, these nine months.

PF: Well (laughs), this is a little crazy. I was sleeping, but in the day, I was living in Austin, Texas at the time, but then we would have these meetings – now I have them all the time – but we would have these meetings with Japan. And so, I was kind of like on a 12 hour shifted work schedule. But it was exciting. So, we built another system. One of my colleagues in Japan, Yasuyuki Kano, he kind of led this other effort to build a system. There is all this debate of, like, how is the best way to do this? So the one with individual sensors, if something goes wrong with one of them, you have a backup, the other ones are going to continue to record. But the downside, the cons — pros and cons — the con for that is that you have to pull them out of the ground to get them. There is a suggestion from GPS measurements on land that even though the fault slipped 50 meters at this location, there is some suggestion that maybe the fault was continuing to slip about a millimeter per day. Well, if we have our sensors across the fault, we want to leave them six, nine months down there. So maybe the fault grabs hold of our sensors. So, then we built this thing into the rope itself. We call them weak links. So essentially, points that are weaker. The rope itself is stronger than steel. But these are points that are designed to break, so that if the fault grabs onto the sensors, you pull hard enough, it will break. And maybe we can get it, breaks above where it’s stuck. Maybe we can get some of the sensors back.

BMR: And that itself gives you some information.

PF: Yeah, sure. That gives you a lot of information. It’d be interesting to know if the fault has moved.

BMR: So, you were leading or at least really, really involved in this initiative of the observatories and the sensors. Were there other teams of people preparing other the things for JFAST?

PF: Sure. My colleague Yasuyuki Kano was building a separate system. So the other system had a single data logger and a bunch of sensors programed onto a cable. And they all went to one single data logger. One problem with that is that you don’t know where to position those sensors. But also, with that, they put it into the pressure chamber. You asked if we did any pressure testing. They put that into a pressure chamber. And for some reason, I don’t know why, but the data logger, when it was under pressure, did not record correctly. So, we just said, “…too risky”. That’s the problem. If you only have one data logger, something goes wrong, you don’t have any data. So, we decided not to do that. We were going to have two observatories, and the other one also had pressure on it. So, essentially, I call them straws – my colleagues cringe when I say that –, but these straws that go down at different depths and they transmit the pressure to gauges up on the seafloor, so you can measure the formation pressure at different depths. They had one built or some machinery that was kind of going to be used, perhaps for a Nankai one [expedition] or something like that. We were able to build one of those, or get that equipment to do that. In the end, well, many things happened. That’s a whole other story; the story of what actually happened to JFAST. But, a lot of things meant that we decided not to do it, too high risk with those things. Again, keep it simple. As simple as possible. And it was a miracle we got any observatory. We got this one, the one with the temperature sensors. Simple design, straight end casing with a string, rope with a bunch of temperature sensors on it.

BMR: When I saw you in Shimizu (port) with the sensors, I realize it’s a very manual work. It’s not high tech, just wrapping…

PF: Wrapping tape around stuff, yeah. For JTRACK we were able to get the rope and with little splices or little loops, kind of seized into the rope at different positions. We were able to – there’s a very good rope manufacturer in Japan, Tokyo Seiko Rope Company, and they can do all this stuff. In the US, we have good rope manufacturers, but I had to do all of that for other – for Hikurangi I had to do that. So, I had to learn all these old sailor tricks from Kier Becker and other stuff. How do you splice rope and how do you make all these knots and loops, and attachments? So, yeah, it’s a lot of kind of manual-type things. Actually, in the end, I felt like I was knitting or something, but, yeah, it’s quite interesting and fun.

BMR: You said there’s a whole other story on how the things went onboard.

PF: I know, you mean in the intermission.

BMR: Maybe we can split and in these two phases. Today we’ve talked about the all this planning phase. And tomorrow we can talk about the actual expedition.

PF: That sounds great.

BMR: Do you want to add something else?

PF: Sure. Well, I guess the main thing is that, with all that, we were able to get a little funding for sensors and such. And we were able to get the expedition set. We got a lot of help from experienced people that thought about earthquake physics, some people with IODP experience, to come up, and have co-chiefs and other things, and build a science team, and we set sail April 1st, 2012. That was one year and two weeks after the earthquake … three weeks after the earthquake. Just a little over one year after the earthquake. It’s amazing that it was possible. But we set sail.

BMR: To be continued tomorrow?

PF: Sure.

BMR: Maybe you were more relaxed during the expedition than during the planning phase.

PF: The stress level increased for another year, and you will hear the story. We didn’t do almost anything, for the first month of the expedition. We didn’t core anything, installed nothing for the first month. Prety early on, they said, “no observatory, we don’t have time”. Then, later it was, “maybe… we can do something”. We lost an LWD tool. No observatory. Well, maybe we have a little bit of time and we can get one in. Maybe the simple one, just temperature sensors. Underwater tv camera – every time we ran it; the cable would break. And so, there’s a little cable there, and each time we run it down – here it goes another one. Hours of fixing… and in the end, no underwater TV. Impossible to put – why put an observatory, it’s impossible to thread the needle. It’s always impossible to thread it, you are going blind, you can’t do it. No observatory. “Sorry, Patrick”. Well, I guess it is… getting a job, some other, a real job.

BMR: (laughs)

PF: But that’s were a lot of people behind the scenes did a lot of work and made it possible. Made a special extra JFAST: 343T, extra expedition.

BMR: But don’t spoil tomorrow’s story!

PF: Spoiler alert! (all laugh)

[end part 1]

Beatriz Martinez-Rius (BMR): Okay, let’s recap.

 Patrick Fulton (PF): Sure.

BMR: The other day we talked about your undergraduate studies, your interest in Earth sciences, and then we went into the organization of JFAST, the development of the sensors, the science and the money. I think we stopped in the moment JFAST started, in April 2012.

PF: That’s right.

BMR: But I think that you wanted to go back a little bit.

PF: Yeah, a little bit. So, we got the okay, the approval to go set sail. We got some funding to buy some sensors, and to also do the type of work of putting together and building an observatory. So, getting all the nuts and bolts together, and kind of a little bit more on the design aspect of it. So that’s where we worked with all our IODP buddies. Rob Harris, one of my mentors, had experience measuring temperature in boreholes. He gave us some guidance. Talking to Andy Fischer and Keir Becker about how they attached sensors to ropes, and stuff. We had some ideas with that. We went out and we try to find companies that can make these really super-high resolution sensors. With everything we’re trying to do redundancy – no one’s really pushed it to these limits. So, try to find two different vendors. And there are two different ones out there. We did that, but it meant they had to turn it around very quickly. We were trying to set sail in April, just a little over a year after the earthquake.

But then, also all the nuts and bolts of who else is involved. And this is where people at JAMSTEC, the engineers that said, “Okay, this is what you want to do? You want to hang sensors down in a hole? Okay, well, this is how we’re going to. We’ll build and design the wellhead. We’ll design the casing. We’ll put all those things together”. One of those people is Nori Kyo. He’s an engineer, working particularly with Chikyu, doing expeditions. He calls himself an engineer, but I really think of him as a technologist. He thinks about, “what is it that you want to do?”, and he uses a combination of oil industry stuff, just other types of engineering-type things, all the other people in JAMSTEC, and building things, and puts it together. And so, with him, Namba-san, another engineer, Muraki-san, someone who knew how to splice ropes, they were the team that really helped build this together, made our dreams come true, “this is what we want to do”.

All that was going on, in many meetings over night, as people pushed the project forward, another group of us pushed the observatory forward. And, now we were ready to go for an expedition. It meant, building a team. So other people, like Emily Brodsky and Shuichi Kodaira, they consulted with a lot of people, including a lot of the PIs on the NanTroSEIZE project who had experienced drilling into fault zones and other things. And I think it was very… interesting and kind of them, to give consultation and advice and everything, but not to be like, “yeah, we know how to do it” and just jump in and say, “we’ll do it for you”. They provided a lot of guidance in the background on things. And so, they built a team and they put together co-chiefs: Jim Mori, an earthquake physicist who is a seismologist, who is very much interested in kind of promoting this idea of drilling into a fault after an earthquake, and Fred Chester, a real fault zone geologist who had some experience on Chikyu, I believe, and also with other projects; working a lot on the San Andreas fault, looking at the physics there. And then, they built a team of field geologists and other things, old folks and young folks, to really put this project together.

On April 1st, we set sail – I’ll tell a little bit more about the team, but on April 1st, 2012, we set sail. The objectives of the expedition, roughly two months expedition – 54-56 days or so – was to drill across the fault, log it, figure out where the fault was itself, maybe measure some things about the stress there, find the fault so that we could put an observatory in there – maybe two observatories, was the original idea. And then, also core. Take core sections out from the fault. So, this idea of trying to find the fault, and characterizing that stuff, needed a team. So, logging specialists, some of them fairly young, but great logging specialists. Sanny Saito, staff scientist in Japan, came. A young Marianne Conin came out as an expert at stress mechanics. Louise Anderson, experienced logger. Tamara Jepsen… a number of people came out here. We also had a team of field geologists that could look at the core, identify the core, maybe also help in identifying it in the logging data. Some of them very young, Jamie Kirkpatrick, Christine Rowe, super already at that stage famous, fault zone geologists. But also, amongst all these people, there is also a team of the friction people, the rock mechanics people that kind of think about what was going on in there. Lots of young folks and a few experienced people like, Fred Chester, Jan Behrmann. But most famous of them all – I’m getting to it – is that we had Casey Moore on board.

Casey Moore was one of the first innovators of studying subduction zones. He was long retired by that time, but he was able to come out, and helped us in trying to interpret and find the fault. Many of us, at least on the US side, were somewhat connected to him. Either for our advisors – he was the advisor, or our advisor’s advisor. He was that way connected, and just a lot of the science that we were thinking about were the things that he had innovated and thought about, and had experience with. So, that was our team. We set sail.

Maybe you can ask a question, but I thought maybe I would think about, from my limited view of what we were trying to do, at least what I was trying to do was: to get an observatory in the ground. So, to do that, we needed to get a general idea of where, from seismic, the down going plate is.

BMR: I was actually going to ask you what was the knowledge at that time of where the fault was? And thinking about that this can be read by people who doesn’t know about the composition or structure of the seafloor, how can you identify where a fault zone is?

PF: It’s not easy. We have seismic reflection data that essentially tell reflections through the water, and then under all the rocks and the layers in the rocks underneath it, that give us reflections that can tell us where things are. But it can’t say, “Oh, this is the fault zone”. We could say, “Oh, that is one thing, and that’s another thing”. The Pacific plate. The rock before they enter the subduction zone has basalt, like volcanic rock created at the mid-ocean ridge, and a bunch of sediment that fell down on top of it over time and built up. We could see the characteristics of that, and we could see that basalt, and then we could see this whole mess of stuff, kind of like a snow plow, it builds up this big pile in front of it. We could see as that in this cross-section of that basalt diving down into the trench, and then has this big pile of stuff above it. So, we could track that thing, basalt and other things, “that’s definitely the down-going Pacific Plate”. We could identify that beneath our site, somewhere around 850, 900m straight down, if our conversions of the speed and acoustic velocity of the sediments above were right, seemed like it was about 900m down below there. But the fault might not go right through there, it might go through some of the stuff up above it. Probably does go up through the stuff up above it. So, that’s what we were aiming for. That’s about what we had.

BMR: Had it been previously attempted, to drill across a fault zone? Either on mainland or at sea.

PF: There have been a few places where they’ve tried to drill into faults, through scientific ocean drilling. Barbados – I’m not sure if they actually got into the fault itself; Costa Rica, not after an earthquake, but into some fault zones.

BMR: So, the important point of this expedition was that we are drilling a fault zone after an earthquake.

PF: That’s right. And that experiment had been tried before, too. I mentioned that I was personally involved in a project in China that tried to do this. There was also an attempt, two attempts, after the Chi-Chi earthquake in Taiwan, in 1999. But the first hole was done – I don’t remember the first one – maybe within a year, but it was only like 300m, and they measured the temperature once, and then the hole collapsed. So, they see a small signal, and maybe that’s just fluid flow. Who knows? Maybe. And then, they said, “Oh, we should really try to do this experiment”. It took them six years to get around to getting funding and other things, and actually drilling, six years later. They could see something, but again, they measured it once and it’s probably just changes in thermal rock properties, but some people have interpreted it as fluid flow – so, not a clear answer.

This was a lot of the inspiration of like how do you do this and how, you know, let’s think about it before the earthquake. So, that’s where we’re at. We’re trying to do that. But here, don’t forget, we’re a little bit different than on land. We’re in seven kilometers water depth. So, to put an observatory in there, we’ve got to first drill down there, use logging tools to figure out where do we think that plate boundary fault is? If the plate boundary fault is the one that slipped, but where is the main plate boundary fault? And then, we have to put temperature sensors in there. To do that, and this is a really important part we were talking the other day, you need to first build a big tube. We kind of said that we’re talking other day we put this tube that’s just about the right width to give a big hug around this big tube, this conductor; may give it a big hug, and then you connect it to a drill pipe, and you go down to the seafloor, and push it into the seafloor. And then, that keeps some kind of an opening so that it can go in and out multiple times. With that, then, you can bring the drill pipe back up, put a drill bit on it, go back down, enter that pipe – which is a thing in itself, we’ll talk about – drill down across the fault, come back up again, and that round trip going all the way down to the seafloor and back at the time took three days, just screwing all the pipe together.

Once we’ve done that, come back. The hole was there. You build a casing or a tube, a steel tube that can hold your sensors inside of it, with a wellhead. And you put your sensors inside, and then go down there, and try to thread the needle one more time, and then place it into to place beneath the seafloor. So, that’s a pretty big ordeal. This is a lot different from what had previously been done at these types of water depths. In the Marianas [Trench], they took a little one meter core, maybe a three meter piston core, essentially. So, yeah, this is a big deal.

BMR: What was the difference with NanTroSEIZE?

PF: Oh, NanTroSEIZE! They also drilled across faults, in NanTroSEIZE. Although in NanTroSEIZE they were not trying to go after an earthquake, or immediately after a big earthquake. There have certainly been big earthquakes, in that area. There are some very interesting stories at NanTroSEIZE. But the water depth is a lot shallower, maybe three kilometers or less.

BMR: Was JFAST your first time on Chikyu?

PF: This was my first time on Chikyu.

BMR: What were your first impressions?

PF: I had a lot more space to move about than on the JOIDES Resolution. It’s just a massive, huge ship; just very impressive, yeah. I don’t remember… Well, I do remember, but I don’t remember what my first impression was.

BMR: So, let’s talk about the “during JFAST”.

PF: There were some challenges. Sure, we were able to get there one year after the earthquake, but seven kilometers water depth – we had to get everything ready. We had to get the observatory ready, but also on the drilling side: the people, the drillers, engineers, and many more things; they had to get Chikyu ready for it. Seven kilometers of water depth, plus maybe a kilometer of drill pipe. That is a lot of weight underneath the derrick. It’s a lot of weight for just the drill pipe, just a lot of tension. They had to get a special pipe, stronger pipe for the tallest part, or the top part, when all of it was employed. Just so it had to have the tensile strength to hold it up. It also meant that we were limited in the ocean conditions out there. And, in the end, we had a lot of “Wait On Weather”. We had a lot of bad storms. But if it started twisting too much, started twisting the pipe, there was a real fear, with all that weight on the pipe, that you’d just snap it and that would be “Game Over”. 

The other thing, too, is that the weight of pipe, the usual weight that you handle, you screw, you’re spinning it or other things, and then maybe you put it down and you have these little slips that hold the pipe on the drill floor so it can hang beneath you, as you screw another part. With so much weight on it, those regular slips that you would use would just crack and implode. They couldn’t stand that weight. So, what do you do, when you’ve got so much stuff on there? Chikyu had to come up with another system, and they had this system called a dual elevator system, essentially another way to – with robots, essentially, grab on to the pipe and somewhat robotically kind of move things up and down, just to hold it together.

Oh, and one other thing. When we were trying to later on put things on the seafloor, and then maybe go back into the hole again – we could talk about that story – that’s a very tricky thing. You need to see underwater, so that you know you’re in the right spot. So, there’s an underwater TV camera with a long seven-kilometer cable that allows you to transmit the video back up to the surface. These are three things that all we need to think about. And they all gave us trouble at the very beginning.

So, before we even set sail, the people are kind of learning, kind of fine tuning the dual elevator system – the thing that can hold the pipe and rack it up. It wasn’t working the greatest. We set sail, and already with that, it seems like we’re maybe already a little bit behind. And so, we set sail, and we already have a Wait On Weather. Weather conditions are too rocky. We have a very tight schedule to be able to do all the things that we want to do. Logging, coring, observatory installation. So, we’re already kind of behind schedule. With the trouble also – the underwater TV was acting up; we didn’t really get a lot done for like the… We have a two month expedition; we do not get a lot done for the first month of the expedition.

One of the things to kind of save time was to, okay, we’re going to find the fault. First thing was to take that tube, let’s give it a hug, and put it down on the seafloor connected to the drill pipe, push it into the seafloor, so we have a tube that we can reenter. And then, we’ll reenter that with the logging tool, and we can go log the hole. Then, in that same hole that we drilled by logging, we can put the observatory straight in there. Two things into one hole. If we identify the fault, it will be exactly where it is. It’s the same hole. So that’s like the first thing after weeks of waiting on weather. We go out, and we put that tube down on to the seafloor, push it in, and then we go to release from that thing. And that involves like putting a dart down to the bottom that as you circulate water, it creates a pressure, pushes out, releases this mechanism, and it can release the drill pipe from it. It wouldn’t release. So, finally we’re able to do something and it’s stuck. It won’t release. We got it in the ground, but it won’t release. So… We had to just pull everything out. We had to pull it out of the ground, brought it, bring it all the way up to the surface again, and then it’s like, “Well. It’s clearly not going to be two observatories. There might not even be one”. We just don’t have time. We’re like a month in.

We abandoned that for a while and we just drilled with our logging tool. We logged the hole. And it’s kind of, “Yeah, it’s probably not going to happen, but just in case, in case maybe something happens and we get some extra time, make sure you put another one of those big tubes on the ground”. That’s the message we got from shore.

BMR: Onshore is at JAMSTEC?

PF: JAMSTEC, yeah.

BMR: And put another one, is to keep another one…?

PF: They wanted to put another one of those tubes on the seafloor, so that we could at least have the infrastructure to maybe put in an observatory later on.

BMR: The wellheads that you can see from the underwater TV camera.

PF: Yeah, this is kind of like the first half of the wellhead. So, this is what the wellhead sits into. We call it a conductor pipe. That’s kind of like the bottom part that reaches underground of the wellhead. So, they said, “Just put that on the seafloor. Go do the other things. Just do that, so that you can –” Oh, actually, I said do it, and try again. Try it again.

So, we went – Oh, I wasn’t going to tell this part! – We went and we try it again. We put it. Released. “Beautiful!”. Now, we’re going to do a real quick job with the logging while drilling tool, just go down and get to the spot where we thought the fault was. And we do that. On a beautiful day. Things are going right. We reenter the hole, and that’s a whole story of how you do that. But we reentered the hole on a beautiful day, logging, logging, logging, logging, logging… Marianne [Conin] comes up to me and says, “Patrick, we lost the logging tools”, I mean, “like the signal, the real time signal?”. “No, we lost the logging tools”. A piece of the pipe, a particular part of it, broke or was broken and essentially, we lost the logging tools. So, now we have that other conductor on the seafloor down there, but we have a logging tool in it. We can’t use it at all. We also lost logging tools. Well, now there’s not going to be an observatory.

BMR: Did you try fishing them?

PF: It was not really kind of possible. So, I said, “okay, there’s not going to be an observatory”. That was pretty much it, then. Well, just in case, why don’t you just put another one of those conductors on the seafloor? So, we put one of those conductors on the seafloor. We got through, and then we moved on. We’re a little over a month into the expedition.

Why don’t I back up and tell the story of how – I guess this is going to happen at some point – I just find it amazing to reenter one of these holes. It’s like crazy. It’s like seven kilometers of water, and people think, or I might have thought that you have like a motor, or something like that, and you move it over that way, and you steer it, or something like that. Or you have like these thrusters, like docking the International Space Station, you know? It’s just hanging underneath there, like a wet spaghetti, you know? And so, and this is like, you can hug it, that’s about the size of your hole and your bit is about nine inches [in diameter]. And you’re trying to do that. It’s wild.

BMR: The wet spaghetti, I like that.

PF: Yeah. And then, I got to go into the dog house where they do this. And essentially – you probably all know this story, well, first you’ve                                                                                                                                                                                                                                                               got to find the wellhead on the bottom, and that could take a long time. But once you find it, you’re like, “oh, I think it’s over there.” So he calls up to the captain and he says, “okay, ten meters to the east”. So, the captain moves that way. And over the next few minutes, he sees like a spaghetti noodle, it swing over that way. And then, “oh, five meters to the west”. Okay. Over that way. And then, this kind of moving back and forth until you’re right above it, and then someone says, “now, now, now!”. And the driller has like this little thing, and he lowers it in.

Actually, we’ve been talking about operations all this time, and it might seem pretty straightforward, but – we are seeing it these days – it takes twenty hours to pull out the pipe. It’s just incredible, because it’s a combination of cutting-edge technology with things that are very mechanical.

Yeah, absolutely. So it was a long time before we even got data, and while we’re trying to do all these things – I’ll step back and say that we got the logging data and then… There’s famous pictures of all the logging data printed out, like life-size scale or something. Not 1 to 1 real time, but scale down, and people just staring over it. And Casey Moore of all people said, “That’s your plate boundary fault”. Many people are looking for a particular type of feature. It’s complete opposite. He’s like, “No, that’s the plate boundary fault. This is why”. And he was right.

BMR: To what did he look at?

PF: Well, let me think this through. Usually, when you look for like in resistivity, there are these 360 degree images, borehole images of the wall of the borehole. And you can see where it’s more resistive, sometimes. And some of that is because there’s different layers, or fractures and such, and maybe there’s more water, and salt water is more conductive. So they see these conductive features; often when you have fractures that are filled with a little bit more water, or clays, or something… And we did see some faults and fractures that look like that. But then, there was this zone that was resistive, opposite, and it’s probably because it was more compacted in other things. Who knows? But the other thing was that, we talked about the incoming plate in the basalt. On top of that, there was another drilling thing at pretty deep depth on the incoming plate, north of us quite a bit, but on the incoming plate off of Japan, in the 70s or 80. DSDP times. They had done logging, and they had seen that there is, on top of the basalt, there is a chert layer, a bunch of clays, and some other mudstone stones. So, the chert layer and the clays had particular geophysical properties. Gamma ray change, and other things. So, right underneath that kind of resistive fault, big change in gamma ray indicative of, “hey, that’s the clays” and then, we got into chert, when we stopped drilling; we kind of can’t drill through it. So, it’s like, clays from the incoming plate, we certainly hit chert, which is certainly the incoming plate. Looking at differences of bedding, and fractures, and stuff like that. This is clearly the plate boundary fault or like, been the long term major… There certainly are fault zones all throughout the system, but that’s the long term plate boundary fault. Amazing.

So then, we’re not going to have an observatory, right? We put in this other thing down there. We go do some other things. The other thing that I hadn’t talked about, all throughout this thing we’re going down, and trying to put one of these conductors on the seafloor, try to go back inside, or I guess we went back inside with the logging tools… Every time we go up and down with the underwater TV camera, it kind of gets twisted, or other things, there’s some problems with it, it will spin around… And we bring it back up, and we have to untwist all this fiber optic cable and other things. And it takes hours. And every time we do it, and probably just from the weight of it, just seven kilometers out and the whole thing is out there, it kind of gets crunched, and crunching fiber optic cable is not good. Inside it are, I think maybe eight little hair-like cables that go through, and you need like three to be able to see down there and communicate. Every time we’re going up and down, we break another cable. And so, we’re like, “okay, we’ve got six”, “we’ve got five left”, “four left”, “three left”. “We’re out”. No underwater TV. So, even if we wanted to do an observatory, we’ve got the conductor down there, how do you reenter that hole? It’s amazing that you could do it when you can see it, but when you can’t see it, it’s impossible.

BMR: How were you emotionally, at this point?

PF: I don’t remember a lot of things; I forget a lot about it. But that part I do remember. I think it was amazing. You have a whole crew out there for a bunch of scientists, and they’re not doing anything for a month. But somehow, I think everyone was in the mindset of, we’re doing the best we can. This is amazing. And whatever we get out of this is amazing. So, for some reason, we’re all just kind of in the zone and just be like, “we’re trying our best”.

Ah! I didn’t tell this part of the story; for with the funding part. So, we got funding for the sensors and stuff. I had the freedom, I could work on this project, because I had a fellowship at the University of Texas, Institute for Geophysics, that essentially allowed me to do what I wanted, to do my own science. But it was limited. And so, I need to like, I’m trying to find a faculty job or a real permanent long time job. I’m not putting in proposals for other big projects at the moment. And so, my funding is going to run out, and so might be “game over”. So it is. We approached funding agencies for funding the sensors, funding the analysis; and everyone’s like, “Too high risk”. “There’s no way that’s going to work”. “There’s no way you’re going to get an observatory on the ground” … And, in some ways, they were probably right. It was very risky. And at that point, maybe we weren’t getting the observatory on the ground. And so, there was a foundation, the Moore Foundation, Gordon Betty Moore Foundation – Moore is the founder of Intel, he is a billionaire, so he has his foundation. And that really kind of tried to fund high risk, high reward things that are generally not able to be funded elsewhere. And they are not one of these people that has an open call for proposals, but we kind of got in touch with them and said, “hey, we’ve got this thing”. And they said, “yeah, we like high risk, high reward. But… This is a little too high risk for us”. But, again, it was another one of those things where they didn’t say no. So, they just said, kind of keep in touch. So, we kept in touch and especially once we were going to go out there, we had the expedition going, they said, “Okay, here’s the deal. If you can get an observatory in the ground – great, if we’re able fund it from somewhere else. If you can get an observatory in the ground, we’ll pay for the analysis”. And essentially what that meant was, this proposal led by Emily Brodsky involving me, essentially paid for my salary for five years, to go and work at UC Santa Cruz on this project.

And so, I have that in the back of my mind. People at the beginning being like, “hey, I hear you’re moving to Santa Cruz” – if we get an observatory in the ground. So, that’s a lot of up in the air and other things; and knowing that we’re putting things in the ground, hopefully – we might not get them back, we might not have anything at all. So, just a little floating, I guess. Very nervous. That’s how I felt.

I guess a lot of it, at that point, is a little bit Zen. You just got to ride it out, and not respond. It’s meant to be. We’re going to do all that we can. And I think that’s what everyone did. That was in the mindset of, we’re going to do all that we can to make it work.

Going back to Casey Moore. I’ve heard about him several times, by several people, so I know he was a big influence for many people. Especially in that expedition.

Yes, right. This was Casey’s last expedition. Casey was retired, probably ten years retired, and just an incredibly kind, gentle person. And had no ego in it or anything. Was just like, “let’s try stuff out; isn’t it cool? Isn’t it neat?” Especially a lot of the young geologists were his proteges; came in the lineage of his thinking of subduction zones, both in the field and also on the ship. It was great to have him out there. Unfortunately, he died just a few years later. It’s very sad, but, but it was really good to have him out there.

So then, we drilled across the fault. No observatory. Can’t even see down there. All these geologists on board (laughs), “okay, Patrick, we like your observatory and everything but…”. So, we started to drill. We’re limited on time, so instead of drilling the whole thing, we targeted intervals, particularly from what we see in the logging. Again, wait on weather; we had some huge storms. 14 meter waves. Remarkable. They turned the ship so that the one wall of the ship would just hit the waves. They lock up all the windows, we can’t take the elevators… It roared through here, it was like, “roaaaar” as each wave came through. Pretty interesting.

But, it did mean that we would have to pull up the pipe and other things. So, at one point in time, Sean Toczko said, “Hey, Patrick, come. Since you can’t have an observatory and you have all these sensors, is there any way that you can measure temperature in the drill pipe?”. When you first drill a hole, you’re like circulating all this ocean water, to get all the chips and broken up rock out, so it disturbs the temperature. So, it’s not that great of a temperature survey, right? But then, why not? You know, we got these sensors and they’re not going to be used for anything else. So, a few of them measure both temperature and depth or hydrostatic pressure. So, while we’re just waiting on weather, we took a core barrel and put a sensor in and just dropped it down to the bottom of the pipe, that’s like sitting in the ocean just on a wait on weather. And we brought it back up, to see if it survived, and… Let’s see if it recorded temperature. And it did. It was beautiful. We could see the whole water column through it. So, I was like, hey, this is neat. Maybe we’ll use that later, when we’re done with coring, we put it in the core barrel, and we can monitor temperatures as we bring it back up. So that’s what we did. There was an interesting thing in that data, and this goes to the coring; is that, when we pulled it up with the core liner, I could see that the pressure, the depth measure, was not just going straight up; is going up, and then going up and down, up and down, up and down, up and down, up and down. And that’s because seven kilometers, or however many kilometers at that time of drill pipe, or of core liner and everything, it’s just like a giant spring. It’s a spring, and so you pull on it, and you pull it real fast, and it goes (straight up), but then it goes, “boing, boing, boing…”. Bouncing up and down. It was interesting, but it didn’t really matter until later. It’s like, “Patrick, it’s enough with your temperature stuff and the observatory. Let’s get to the real coring geology”. So, eventually the wait on weather is gone, and we start coring. And the cores are in a million pieces, all broken up in all different parts. So it’s like, “Oh, well, that’s really interesting geology”. But it’s also sorted, like all the fine stuff on the top, all the coarse stuff on the bottom. For two, three, four cores, it was like this. It’s terrible. It looked like someone just took a core sample, shook it all up, and then let it resettle. Not what you really want. So, what we determined was that, we’re pulling the core barrel, and the whole thing’s shaken up like a spring. Something that had been seen before in industry, although they don’t core that often. But, something that you have to think about, and the drillers, when you’re at these extreme water depths. So they don’t have to go slow the whole way, just have to ramp up.

BMR: That’s very interesting, because it shows this process of learning while doing the actual things that it’s so common in scientific ocean drilling. You plan something that has never been done before, and then you start learning from the mistakes. This is a great example; and it just came up because you had some sensors on a rope…

PF: Yeah, because we had some crazy experiments (laughs), and then, just thinking of those two things together, and realizing, this might be what’s going on. I’m just a postdoc – I’m young now, but I was even younger then (all laugh), and going up to Sean and being like, “hey, I could be wrong, but I think this might be what’s going on”. Because clearly, we’re not fixing it. We’re not being able to figure out what’s going on. And so he said, “yeah… Why don’t you show me…”. And he brought me with my laptop into the doghouse and said, “Explain this to the drillers”.

And it’s not all just about me, but that’s the story that I know. But yeah, then we started coring and continued on, and were able to get better core, finding different things. And then – this is like the movie part. There was a total solar eclipse. We were in the perfect position with Chikyu. Total solar eclipse. We haven’t had a lot of success. We’re kind of moving forward in small bits, trying to catch the plate boundary. Shorter and shorter advances, we’re running out of time. And, you go out there. And there was a total solar eclipse. I have this picture of Casey Moore looking through glasses or whatever, but this big, like, welder’s sheet or something like that. And, his former student, Christie Rowe, holding it for him. And they are looking at the solar eclipse together. And just a few hours later, we got this core. And it’s like, “Oh, that doesn’t look like anything at all. There’s not much in it”. It’s like weird looking. But when you look closer, that is the plate boundary fault. It’s all like welded together with all these like little pieces, all kind of welded together, and all this fabric of sheer stuff all across it… Yeah, we got the plate boundary fault. Amazing yeah.

We went further and got more core. Ah, with this, too! I think when they said, “Even though you probably aren’t going to do it, put another one of those conductors on the seafloor, even though we’re probably not going to be able to do things”. I think… We had amazing co-chiefs. Jim Mori and Fred Chester, they were the epitome of like how you do leadership. We would have these long meetings where they probably already made the decision on something like that. And they listened to us, and we would talk things through. They really involved all of us in that process. And so, part of that, and I think from shore, was trying to find some extra time, maybe at the end, that maybe we could go in. When the underwater TV camera went out, it was kind of “game over”; but essentially trying to continue to make it… maybe some hope we could still do the observatory, including – you know, we’re running out of time, and the other thing they say, “put one of those conductors on the seafloor, we’ll give you some extra time”. This is from shore. “The expedition is scheduled to end on this date; we cannot change that date”. But instead of going back to port, we’re going to allow you to stay out there for 2 or 3 more days. We’re going to fly everybody out, work to the very last minute, fly everybody out on the helicopter.

And that’s what they did. We worked to the very last minute, analyzing the core, getting samples and other things. The report writing – everyone knows you can’t leave until the report is done. We were essentially quarantined. We all got onto the Shinkansen, were shipped down to Yokohama. And then we had a day at Yokohama where we finished up the reports in Yokohama. And so… We also had a very big party. That was JFAST [?]. Tomo-san [Saruhashi], there’s a big photo of him, he might have a giant beer in one hand, and he has a cell phone in the other one. And essentially, he’s talking to, I believe – in my version of the story at least; it can be a totally false memory – but there’s a photo he’s on the cell phone – could be totally unrelated –, but at that meeting, or at that party, we’re all celebrating, we got the plate boundary fault, we got data that can tell us the stress state and other things. We didn’t get the observatory. So, it goes. I had already heard a little bit beforehand, but they announced at that meeting: We’re going back. To do the observatory. So that’s where 343T, JFAST 2 comes in. They couldn’t do it right then. Underwater TV is still broken. And also, Chikyu is partially broken. Chikyu had, during the tsunami, one of its thrusters got ripped off. And so, it had a schedule in drydock on the complete opposite side of Japan. It had to go all the way back there and do that. And then it had a scheduled kind of, non-IODP research thing for gas hydrates. So, there is a month gap. We said, “okay, we’ll come back”.

Jim Mori is co-chief, and I went back out in July of that year. And we went back out to really deep water, and they panned out all this fiber optic cable, corrected it, re-spliced and everything, fixed the underwater TV camera. And now, we’re back in business. So, we went back to that conductor pipe that we had on the bottom. We ran into the hole, drilled down across it, came back up, built the observatory underneath it, put the sensors in, and installed it on the seafloor.

BMR: Were you the only scientists in 343T?

PF: The only scientist beyond Jim Mori, who was also onboard.

Dan Brinkhuis (DB): You mentioned yesterday the story about going straight to a press conference. Was there a lot of media attention over it?

PF: I don’t remember that part, but there was a lot of media attention on that.

DB: I remember someone told that it was like one year after the tsunami, that the press was kind of interested in the results, so [Shuichi] Kodaira-san went straight to the press conference.

PF: Yeah. I don’t think that was me that told that story, but that is what happened.

BMR: Can you tell us more about it?

PF: Yeah, I don’t remember a lot of the details of it, but essentially when we got off the ship, well, there was certainly a lot of press attention, including a very famous picture of the core with Jim Mori, Kohtaro Ujiie, and Marianne Conin looking over at the core, you know, looking over our success. And there was a lot of attention. Honestly, we succeeded, even without the observatory. We went out to do some impossible things, and somehow we were able to get the plate boundary fault that perhaps created this earthquake, whether it was on that particular fault or some subsidiary fault. That was in the long term plate boundary fault. That was the fault that clearly has had a lot of big earthquakes on it.

One of the questions I had earlier today, just 20 minutes ago, was, what about the other people on the ship beyond the scientists, beyond the engineers? Probably one of the most moving experiences, of the thing, kind of a Zen riding through it… I think it really always hit me, but the one part that really moved me, was at the end, where we had the core out and, this part of the ship, giant ship, this is where a lot of action happens. The science part is closed off. But they gave tours to the crew, to see what we were up to, and to look at the core. And to see people who certainly experienced that earthquake and tsunami or are feeling the effects of it, their families are feeling the effects of it. To see them see a thing that in some ways was the source of that thing, and to realize and to… I think there was a bit of a pride for everyone on board that, you know, we were doing something that, trying to address that, trying to get some sort of common good of the earthquake, and the experience… So yeah, that was a pretty important part of it.

But yeah, there was a lot of press attention. And people were rushed to announce to the world, and to the Japanese public, that we had succeeded. We drilled across the fault, we’ve got samples of it;  those samples that were being rushed to labs across the world to study it, to analyze it, to try to figure out why the earthquake behaved the way that it did… We also had this log data that told us a lot about the structure and perhaps what, the stress conditions there. So, that was about it at that point.

But that party, you know, we’re going back. So, a year later, we went back… Oh, there was another scientist after, I forget! For part of that time, there was another scientist as well, Emily Brodsky. Emily Brodsky, who had been pushing this project all along, saying – or really to Demian, my advisor: “hey, have you ever thought about drilling into a fault after an earthquake? or thinking about hydrology processes?”. Pushing this forward, and people telling, it’s impossible. She was able to come out for the installation of the observatory. And so, it was good. Essentially the three of us, me, Emily and Jim, had a paper in 2009 that said, “you know, it sounds crazy, but drilling across faults after earthquakes is something we should be thinking about.” And here we go, the three of us there, on board. So yeah, we were able to install it.

I don’t know if I talked about all the things, I talked about weak links in there, and stuff…

BMR: That some parts of the rope were weaker, so if the hole would collapse…

PF: Yeah. So, we weren’t in the clear yet. We got in there, but we could celebrate a little bit.

BMR: So, essentially this massive ship that costs the order of hundred thousand dollars per day, was moving because you were going to install the observatory?

PF: Well, it’s really about JFAST, the whole thing. This involved also a lot of people on shore. The silent people behind the scenes: Kodaira-san, Emily… a lot of people within JAMSTEC, and MEXT, the Japanese government kind of saying, “is it impossible? Because if it’s still possible, let’s try”.

BMR: Now that you mention MEXT. Of course you are not the one to talk about MEXT, but I was wondering what kind of feedback did you get from them? Were they supportive, skeptic…?

PF: I don’t know the system of those things. That’s why it’s like, these silent players that are on shore. But what I’ve heard is that everyone in Japan was supportive and trying to do as much as we can to make it work. Claim the success. I think everyone needed a success. JFAST was a success without this. But, you know, getting out there quick, this kind of experiment that we wanted to do, to really push for that… And so, high risk, high reward. On the edge of impossible, it was still possible. So, maybe it’s still possible. So, that’s what got us back out there.

So then, we can relax a little bit. We got in the ground. Is the fault moving? Is it going to capture the sensors? That’s where we were still nervous. So, there was already a plan to go out in October. We got this in in July, mid-July 2012. We planned to go out again in October. We had originally thought that we would get this in in April, mid-April. We wanted a few months so that the temperatures could equilibrate from the during disturbance, and then perhaps see a temperature anomaly across there. So, we got it a few months delayed before we got it in there. I was not comfortable taking the temperature sensors out in October. Maybe it’s all that work taken out too soon. The temperatures are all disturbed, yet we won’t be able to see it.

MP: Can I interrupt with a question?

PF: Yeah.

[change of camera]

I want to know about what happened next in terms of your conversation with the Gordon Moore Foundation. Did they call you?

Great. Yeah, I kind of forgot. Well, that might lead to another story that … a short, very short story. A very short story, about us getting off the ship, you know? So, I don’t know where. Oh, I guess we all got off the ship at the same time.

So, it meant that, we got a hole in the ground. I could be funded, I can move to Santa Cruz. I moved to Santa Cruz, that’s where Emily Brodsky works. So I go work with her there. So, we told the Moore Foundation, they said, “Great. Write us a proposal and think big”. (all laugh) We probably didn’t think big enough (all laugh). But essentially, Emily and I wrote a proposal that essentially paid me to work on this project, to be able to go back out, collect the data, analyze it and such. And both, her and I integrate all this stuff, the hydrology, the frictional heat and stress conditions, and such. So, that’s what I did. I moved out to Santa Cruz. I don’t know if it was immediately. It was immediately. That was in July. I moved in December of that year. Moved out to Santa Cruz. We still haven’t got the data, yet.

But, when we came back in – and this is probably a good way to end for today – we were done with 343T. Successful operation, successful installation. We went up to Hachinohe, to the very north. And probably to save money or other things, they decided not to go into port, and they would stay just outside, and hang out there for a while. A lot of jellyfish or something went through the water filtration system, I remember that part. And they had to scrape all the jellyfish out of the filters or something. I remember that part. But also, it meant that, not a helicopter coming off or helicopter going on. Now, they took the dinghy, the tiny little speedboat, emergency boat, off the side of the ship. Then we got lowered down, like hand over hand on ropes or something like that, down into it. And that thing can only hold like three people. And so, we took that little speedboat into Hachinohe harbor, and like climbed out like this swimming pool type ladder onto the docks there.

We were off. And then, we had asked Sawada-san what is – oh, there’s a famous picture shaking Sawada-san’s hand when we successfully installed this. But, we said, “what’s there to do in Hachinohe?” He says – I don’t know if I should tell this story – but he says, drink and eat (all laugh). So that’s what we heard, there’s not much there except for this one shrine. So we went to the shrine, it’s like the shrine to the seagull or something. And we’re like, “why does everyone have umbrellas? It’s a beautiful day”. Well, it’s because there’s so many seagulls. And so… (laughs) We got out clear.

And oh, this is the last story. “Is there any delicacy, any special food to eat?” And he said, “uhm… sea pineapple”. Okay, whatever. So, there’s this little alleyway in Hachinohe, where there’s all these little stalls, and it has like stools, and everyone has a little thing, and they have their little specialty, and have a drink. Oh, sea urchin, great, squid… We go to this other one that has a little, fruit stand type thing on it. And there are these little things there. “That has got to be sea pineapple.” It’s got like little roots on the bottom. It looks kind of like a kind of looking type thing. Hoya, is what they call it. So, we’re like, “We’ll take one of those”. The woman behind the thing says, “oh, great”. She goes behind the curtain, and gives it to someone to prep. And we say, “animal or vegetable?”, and she said, “oh, uhm… In between”. (all laugh)

Yeah, it is definitely an animal. A sea squirt, that’s what we would call it. A big barnacle. So, Emily and I celebrated, we earlier had a celebration with Nori Kyo and Jim Mori; they took the Shinkansen and went back home. But Emily and I celebrated over a sea pineapple.

BMR: That’s a great story. Well, thank you very much.

PF: Thank you.

BMR: Should we do a part three?

PF: We should probably get the data, hopefully.

(all laugh)

BMR: Let’s continue where we left off. We were in JFAST T, in July 2012.

 PF: We got the observatory in in July of 2012, and one of my colleagues, collaborators, on this project is Yasuyuki Kano, from University of Tokyo. He was actually involved in some of the trying to measure temperature after the Chi-chi earthquake in Taiwan. And he was also involved in trying to develop another style of observatory, one with a single data logger at the surface that was not installed in the end. But he had arranged to get time with the KAIKO ROV, the only kind of remotely operated submersible that could go down to this depth and pull our sensors back up. So he had arranged some time, thinking that we would install the observatory at the beginning of the JFAST expedition, in April, so he had some time and gotten some time, for a couple days in October 2012 and then again in February of 2013. But we didn’t get the observatory in until July. And so, just a couple months later – that was too soon. When you drill a hole, you kind of circulate cold ocean water, and it’s going to disturb the temperature in the borehole. It will eventually equilibrate to the formation temperatures, but it takes some time, a few months. So, October was too soon. We spent all this time and money in there, we don’t want to pull it out and not be able to see anything. So, we leave them there. But they went down with the ROV, and they saw the wellhead, and there it was.

So, Kaiko can reach 7000 meters.

Yes, it has a another part to it. At the time I knew it as KAIKO 2 7000. Two, because this is number two – the first one imploded – and 7000, because 7000 was the maximum depth that it could operate. And our wellhead is at 6995m below on the seafloor. Give or take a few meters. So, it’s just at the limit, you know, “is it possible?” this is just at the limit of what is possible. So, we were able to use is that one, off of the Kairei ship, we went on board.

So, in October we came back for the second time that we had scheduled for it, in February, February 2013. On the Kairei. I was out there with Kano-san, Jim Mori, and myself, along with Nori Kyo and Muroki-san – some of the folks, the engineers that helped us kind of put it all together. And so we set sail out there. Again, weather was rough and everything. We had two dives and were out there with other scientists who are going through this kind of area, and they have certain dives kind of allocated to them, as well, to pick up ocean bottom pressure sensors, ocean seismometers and other things, maybe put some on the ground.

It can’t always dive on certain days. And so, we go out, and one day at one of our dives, and we go down and just the current is so strong, it just blows off and everything. And we’re like, “but we want to go over there”. That’s where the thing was, but we couldn’t find it. And then, we had another dive. We went down on that dive, and KAIKO only operates during the daytime, so that if it does rip off of its cable or something like that, it’s supposed to float to the surface, and you can find it. So it only operates during daylight. Usually, it’s supposed to be like eight hours or so. And we went down, and we went to the position of where we had mapped, where we left it, “we left it right here”. And we searched around for a long time and we couldn’t find the wellhead, for hours and hours, a hours…

BMR: I assume Kaiko has an underwater TV that is remotely operated.

PF: That’s right. So it’s remotely operated kind of submarine, unmanned, has cameras. We could see the camera vision. It has many cameras, but like two super high-resolution, ultra-high definition cameras. And we could see it. So, we’re sitting on the Kairei, this relatively small ship, it’s pretty much just the cable…. It’s now retired, that ship, but half of it was pretty much just the cable to lower and bring up the ROV. And then, we were sitting at a table. There’s not a lot of space – Chikyu has a lot of space, lab space and everything. The Kairei, pretty much the place for the scientists to work is pretty much all – 12 of us, sitting around a table just like the table right here. And your chair is bolted to the ground, so you can’t really kind of move too much or anything. And that’s just pretty much where you are. It’s a pretty small ship. I was definitely seasick, on that ship.

Side story – maybe I shouldn’t tell this one But I made, you know, you talked about mistakes. I made a mistake on that one. And I made the mistake when they asked me, “Patrick, do we need to make special western breakfast for you?”. And I said, “Oh, no, I love Japan, I love Japanese food”. So, I said, “no, Japanese breakfast is fine”. But that meant that I had fish and rice every meal, and I don’t really eat fish that much except for sushi. But, yeah, fish and rice every meal. And so being seasick and having fish and rice every meal – it was rough. It was definitely rough.

BMR: How long did it take that cruise?

PF: I think we were out for three weeks. We didn’t get a lot of dives. But we used two dives to kind of – you know, some dives were to be able to put ocean-bottom pressure sensors, where we had them float up, and we were able to get some. But three weeks out there, and two dives.

This last dive, we searched around on the seafloor, going back and forth… We could see fissures, like cracks on the seafloor, probably from the earthquake. We searched around. We’re going up and down, going to deep water… And then, at some point, it’s starting to get dark, and aren’t really comfortable with operating – well, we’re not allowed. There was another kind of floor that had all these TV cameras and stuff. And, you know, I was the only non-Japanese person on board, and at some point, pretty early on in that dive, people stopped translating. So, it’s pretty clear that things weren’t going to plan. At the end, we found this big cliff, like a fault. It was clearly a fault scarp of some sort. Not exactly sure where we were. Probably deeper in the trench. Two, three meter tall cliff. This really impressive-looking thing. And then, we just sat down. That was pretty much it. They kind of lowered the ROV down just below it. We just stared at this wall.

Now it’s pretty much the end of that. We came back up and, that’s pretty much our last dive and the last opportunity to find it. And so, just like at the end of JFAST expedition, we were going home empty. We got the observatory in, but we can’t find it. One of the big things, particularly scary about seeing this kind of fault scarp there, is: between October and February — October 2012, when they had seen the observatory wellhead where they thought it would be, and now in February, where we were looking around, “it should be here”, there was a magnitude 7.3 earthquake, pretty much located right at the JFAST site. Not on the plate boundary fault, much deeper, on one of the normal faults in the down-going plate. Pretty deep, but 7.3 earthquake. There was a fear that there was a giant landslide which just covered the wellhead.

The wellhead is about six meters above the seafloor, but you never know. So, yeah, maybe… “Game over”. But… We wanted to be for sure. Is it possible that it’s still there, still accessible? Well, it would be good to know for sure. So, other people who use Kaiko and are going into this area to do other things, people, friends, colleagues, other Japanese researchers, volunteered their Kaiko dives, to have us go back to do a survey. Make sure. We really, exhaustively did kind of a search grid, to try to find the wellhead.

BMR: Did it extend the same expedition, without going back?

PF: No, we went back. So, they had another cruise out there, in that area, in April. So, this was February, and a few months later in April, we went back out. One of the things was that this time, first we would try to go with the ROV not all the way down to depth, where you can only see a few meters ahead of you. This time we would fly kind of above it, and use side scan sonar with it. In addition, and to make sure that we knew exactly know where we were, where we had looked, and hadn’t looked, we used some really expensive transponders, put them in different spots on the seafloor. With JFAST, we had put transponders down. A lot of them imploded because they were rated to about seven kilometers water depth. And they just didn’t handle it.

So here were ones that I think could go to ten kilometers. And put them out, really sensitive ones, just so that we know where we were. So, we went down on one dive, and we did side scan sonar; flew above the seafloor. You can’t see anything, but essentially try to map the seafloor out there. For a few days afterwards, staring at the data, one of the scientists on board said, “I think there’s something, kind of a big echo, or something kind of sticking up over there”. So, when we went down, we thought we saw stuff on sonar and we would go and would be, a fault scarp, or be a boulder, or something. So, we would have all these false, “there it is!”, and go towards it, and there’s nothing there. But this was kind of, “I think that that’s it”.

On the next dive we went down, and we were able to find it. There was. Coming towards us. There it was. And above, there’s like a ring. Like, Lord of the Rings – there it is, kind of shining there. That’s the little ring at the top of the wellhead that we were going to grab on to. And so, Kaiko’s arms came over and grabbed onto the wellhead, took its other arm, and it’s kind of bucket, had like a hook connected to a rope, connected to Kaiko, and go and hooked on to it. We had a little load cell on there, too, onto that rope that could kind of see, essentially, is it stuck or is it not? Because, it’s been about nine months since we put it in. There were indications from some of the GPS on land that the fault might be moving like a millimeter per day. That’s a lot of movement that would shear the pipe, grab, hold onto our sensors. And we had some weak links in there, but could it come out? So, we grabbed on to it, and we started pulling up. And then, as you pull up, you can’t really see any further because you kind of turn, and you get further away from the wellhead. So we can’t really see if we’re pulling out or not. We’re looking now at the load cell, and it’s going essentially ….You don’t have a lot of load on it. Can we break something? And people are like, “no, I think that’s the right load of like the sinker bar, I think we’re alright, in the clear”. And so, this was another long night. A long day for the Kaiko ROV. It comes up, and it brings the rope. We kind of fish it. But there is a storm on the horizon. Of course, lightning out there. We grab it and then, in the night, as it’s getting windier and windier, we’re essentially pulling the rope up with the A-frame, and all these other things, kind of pulling it up onto the ship, and then it seems like we’ve got it all.

There’s the sinkerbar. We’ve got it all, there. And we strap it all down with, like, super tight on, and other things, but strapped it to the deck and get out of there. The captain was like, “I don’t want to be in the storm”. And then, in the morning, a beautiful day. Sun comes up – probably like four in the morning. We go out, unstrap it, look at it. Just double check. It’s all there. It didn’t fall over in the middle of the night – thank goodness. But it’s all there. We lay it out on the deck. We retrieved all of the sensors which, before we even get to the data, is like a scientific piece of science datapoint in itself. It meant that whatever plate boundary fault that we went across there, it did not move a lot or considerably, in those nine months after that earthquake, to be able to get it all out. And people have interpreted that it meant that, there was GPS data that were saying there’s movement. It’s not that the fault was actually moving, but it’s actually an effect of the mantle, essentially churning after the earthquake. The earthquake moved, slipped a lot; now the mantle is kind of catching up at this point, “Oh, you woke me up”. And it’s kind of like catching up with the plate that moved during the earthquake. So that’s pretty interesting.

Yeah, so we got it. Now we start downloading the data, did the sensors work, and such. And I had set it up – I don’t know how I did this, but I set it up in some way that I could remove the background signal to see anomalies as I was kind of downloading, as we were getting more data. I started from the bottom, started to see stuff, and I would plot it up because each time would take some time, ten minutes or so, to download the data. I’d immediately plot it up and see what it looked like. “Okay, that’s the temperature. But is it an anomalous temperature? Is it above what we expect?” Already after a few, I’m like, “there’s a signal here. Well, I don’t want to get too excited”. But the more and more we put together, all the sensors worked, all recorded data, and essentially, at the seafloor, it was like one degree, 1.5 degrees Celsius down at the plate boundary fault or around there, at the bottom of our string, around 820m below the seafloor, about 25 degrees Celsius. Which is probably like the temperature in my bedroom up here, on Chikyu (all laugh). It’s so hot. In the meantime, we measured so many thermal conductivity values; we could kind of see or predict, what the variation in temperature would be, with depth just based on the rock properties, and we could get an idea of what the background temperature profiles was. When we removed that background geothermal, we could see the anomalous temperature. And there is a big, big anomalous temperature right around the plate boundary fault. So, 0.3 degrees Celsius. Our sensors can measure to an accuracy of about a 1000^th of a degree Celsius, have resolution even further down below that. So, 0.3 degrees, pretty stable over many different sensors. Probably like ten of them. This kind of increase across there. And so, that’s what we’re after. The frictional heat signature from the earthquake.

Put that into our models, we had to do bunch of stuff to interpret the data. There’s a bunch of different effects. At first, it was very cold because it’s all affected by the core drillings, circulation… Then, it kind of started to equilibrate and get to this part. When we put it into our models, we can backtrack to figure out, it’s 0.3 degrees now whiich, how much heat had to be put on the fault during the earthquake? Back in March 2011. How much heat had to be put on there? We get some value of how much heat per unit area was put on the fault. During that earthquake, I think it was 27 megajoules per meter squared, which doesn’t mean anything to most people; but that value, the amount of heat per unit area, was kind of what was in our models, or what our understanding of things were, and why we went out to look for with this thing. The amount of heat per unit area put on the fault from frictional heating is directly related to what the average shear stress was during slip, and how much displacement there was. Here, from [?] bathymetry and other things, there was around 50 to 60m of slip in this area. That’s our displacement. And now we have how much heat was put on the fault during the earthquake. If we divide that, we get essentially the average shear stress on the fault during earthquake. I can’t remember what it was, but… The shear stress depends upon how much weight of the rocks is kind of pushing down on the fault. So, as you go deeper and deeper, we think stress is just increasing generally. But what we really want to know is that relationship between the normal stress, the part that’s pinning the fault together, relative to the shear stress that’s trying to shear it. And so, if from density logs, we can figure out the weight of the rocks, if we remove that normal stress and assume some things about water pressure and such, we can get the average friction coefficient.

In the lab, people just kind of crack rocks, they move them, and just see how much it takes with a certain normal stress pinning the rocks together. How much does it take? Shear stress to shear it. And the ratio of those two things, shear stress to normal stress, we call friction coefficient. In the lab, when you just start to do it, at the beginning, it seems like lots of different rocks, most rocks, have a friction coefficient of 0.6. There’s reasons to think that when you go really fast that it might be less, but what is the real value? We don’t know, for a real earthquake.

And so, when we do it, from our temperature numbers and from the weight of the rocks, we get a friction coefficient of 0.08. Essentially it meant that it took very little shear stress to make it slip. So, this is kind of the question that we had at the beginning. Why was there so much slip at the shallow part of the fault? Was it because the fault was really strong and it had built up a lot of elastic energy? The friction was really high and built up all that elastic energy there, it got stuck, and then when earthquake came in, it released all that elastic energy and in the form of slip? Or was it really weak, and the earthquake happened, it came through, and there were no brakes on the system.

Similar to hydroplaning, just kind of went. Our value, 0.08, said there was essentially no resistance. There were no brakes, on this shallow part of the system, when the rupture came through. That’s a pretty big deal.

BMR: It’s interesting here that you reached this important point through the temperature analysis, combine with the study of the sediments and cores you retrieved. But the evidence was given by the temperature – which is something that, for people not expert in this science, can be surprising. Because it’s easy to assume that is only through the analysis of the materials that you get to conclusions about friction, for example.

PF: Well, you could certainly not believe this guy who studies temperature. So, other people did look at the rocks. And so that’s where the whole story of JFAST comes together, is that this part had 0.08. In addition, Kohtaro Ujiie, Matt Ikari and others, took those rocks from the plate boundary fault and they put them into the lab. They said, “Those experiments at low speed, just kind of how much does it really take? What is the friction of it? Well, let’s do it on that material from the plate boundary fault”. When they do it there, in the stuff outside the fault, it might be 0.4 or so. And then, inside the fault, 0.2. But it’s not 0.08. So, a bit weaker in the fault than outside the fault. And there’s interesting reasons why that may be. We can come back to that. And then, Kohtaro Ujiie put that that fault zone material into his high speed friction devices, at speed that you can only sheer a little bit, and you get how much it takes to break.

But what happens in an earthquake where you slip like a meter per second for up to like 50m? How do you do that with like two little bits? Unless you have like two pieces of rock that are 50m long or something? Difficult to do. So, to get that much displacement, instead of just going past each other like this, why don’t we just spin it? And then we can get a lot of displacement across those rocks. So, essentially, with a kind of conveyor that part goes past it over many times. So, this is one scientist, real engineer-type of scientist, Toshi Shimamoto, he designed these devices to be able to do this. Essentially like those hydraulic ram videos on YouTube where they go and they squish Sponge Bob, and it explodes or something. He had one of those things, a hydraulic ram to push it all together. But then why don’t you do that? Push your two pieces of fault rock together? And then why don’t you hook up one side to a motorcycle engine spinning? And so that’s essentially what’s going on here.

So, Kohtaro Ujiie did this in the lab, and he tried to see how much shear stress, relative to normal stress, does it take – what’s the friction that goes on there. He got two different results because he did his experiment slightly different twice. He should be telling this story. But, on the ends of the sides, where it’s the material to kind of hold it there, one set of experiments he put granite, really impermeable, kind of hold onto the sample there. He has like a Teflon ring so it doesn’t go flying out into your face. On the other one, he had sandstone. Sandstone was a bit stronger – it was still pretty weak. But the granite ones were weaker, something like 0.08, just like we had seen. And what the interpretation is, why is there a difference between the granite on the outside? The granite is not shearing next to anything. It’s just that it’s whether it’s permeable or impermeable next to it. And so, his experiments also create heat. And, when you create heat, its also has little tiny little bits of water in the rock there. And the water expands, normally expands. If it expands, then, it creates this extra water pressure that can push both sides apart, make it easier to slip. It’s called thermal pressurization. So, in addition to just the rocks getting weaker as they go, this process of frictional heat actually can drive you to have this process. Actually, just makes you even weaker, maybe next to nothing. That’s what he saw.

So, it’s a combination. All of this stuff, and all the results of JFAST. Is a combination of all the things that we did out there. I’m talking a lot about the observatory; that’s what I lived, and dreamed, and cried over many times. But, there’s the whole picture of putting it all together. And that’s where we’re at, at this stage. At least in the story is that, we see very low friction, essentially says no brakes. He says these rocks – Matt Ikari says – just by themselves they’re kind of weak, a little bit different. Ujiie says, during an earthquake, they can get really weak, similar to 0.08 through this thermal pressurization process. Then, instead of just looking at the fault zone core and other things, understanding the logging and all of the whole bit of how this all fits, and why we’re back here on JTRACK. How does this all fit into the whole large scale, structure? It seemed like the parts that are already a bit weak are in this clay material inside the fault zone, that is a bit different from outside of the fault zone.

Maybe, these weak clays – the rupture comes in, and instead of just dispersing and finding its way through sand and other stuff; the rupture comes through and it finds this weak path. And has no brakes on it, essentially, when it goes through. And just gets weaker and weaker as it goes through. Maybe that rupture, as it comes through, finds this part and just continues along that weak path all the way to the seafloor.

That’s my interpretation of it. But it took the structure, the lab experiments, it took this process in there. So that’s essentially three papers that came out, all together. One led by Fred Chester and all the geologists about the structure of the plate boundary and all those parts; another one, looking at the low speed or high speed friction part; and then the temperature part. All three came out together in Science in 2013. But there’s a fourth paper, as well, that came out. And that’s also from JFAST – well, there’s many papers, but for Science papers. And that’s from the logging data. The logging data showed that … when you drill a hole as best as you want to, you try to drill a cylindrical hole, but the tectonic stresses kind of try to squish it into a, not a cylinder, more kind of oval shape. And it kind of pinches the edges of the rocks there, and it creates like these vertical cracks where it’s kind of getting pinched. And so, we could use those, we could see those pinch points, in the holes in some parts. And based on the strength of the rock, we could try to figure out what is the magnitude of the stress one year after the earthquake. That, when we’re putting all the stresses together, essentially said that, in 2012 when we were out there, there was no shear stress built up on the fault. So, it meant that when that 50m of slip went by, it relieved all the stress. At least on the shallow part. Now, this is maybe completely different down at the hypocenter, where the earthquake started. But at least in this shallow part that slipped 50m, it relieved all the stress. So, that was another big kind of result. Putting all those things together really told us parts about the mechanics, the physics of earthquake slip that we’ve just never really been able to put all those components together.

BMR: Just to bring all these results into context. What was the previous understanding of this events, and how your results changed it?

PF: At the beginning of this whole story, I kind of told you that this earthquake took us by surprise.  I had thought, “Oh, shallow parts of subduction zones don’t really slip”. When we think of big earthquakes, like subduction zone megathrust earthquakes, we think generally about the cartoon picture that we have in our classes which is like, earthquakes starts down deep around the hypocenter, has a lot of slip there, and then the slip kind of dies out until, maybe if it starts to go to the shallow part, the rupture comes up and it disperses amongst all the soft things up there, and maybe causes some deformation in the shallow part. This shallow part is soft and just deforms.

But, a through-going rupture of 50m all the way to the seafloor, it blew everyone’s mind. And so, is that something we need to think about everywhere? Was this special? That really kind of put us in a bind, understanding whether faults… Going further back, people debated whether faults had friction on them, like 0.6, like a brick on a table, or whether they were a lot weaker than that. This suggested that they’re pretty weak. Other questions about when faults rupture through something, do they release all the stress? or do they still hold a lot back? So, this kind of gave a lot of – it’s for a certain particular spot in this shallow part, but it gave a lot of kind of direct answers where we often don’t have direct answers, on these types of things.

BMR: Are you aware if these results have been applied to other parts of the world, to understand where can these sort of big slip earthquakes happen? By people outside the community of scientific ocean drilling, I mean.

PF: Yeah, certainly. One thing maybe I’ll talk about, was there something special here, for a moment? There is a lot of ways where these results have gone into modeling and other things, and thinking about what is possible. Can you rupture through parts that we generally think can’t host earthquakes? Can you rupture through those things? This rupture all the way through this part that we generally think doesn’t host earthquakes. Other parts, like on the San Andreas fault, there’s parts that creep and people think, “Oh, those parts don’t usually have earthquakes”. But if you had earthquakes on somewhere else that could rupture through, trying to think through what happens in terms of stress and friction on those parts.

But, is this place special? This is where it Casey Moore comes in. Casey knew, like when we crossed the plate boundary fault, he said, “In the logging data, I see this big kind of spike in two physical properties. That’s the same as the clays that are on the incoming plate above these cherts”. And so, he went back through the history of all these other people in the Pacific, all these other IODP, ODP, DSDP, all through the Pacific. These people that are doing paleoclimate, not really thinking about earthquakes, they’re mapping all these clays and other things, the stratigraphy. And they map out where are these clays and different things. Casey said that where these clays were deposited, is pretty much like the furthest place away from land that you can get. And what he said was that it’s the perfect place to dispose of a dead body because they’re so deep, that everything dissolves – all the carbonates and other things – like your bones will dissolve and everything that would be left of a dead body would be that appetite on your teeth. But what I’ve heard is that people have found fish teeth in some of these things, and they can do CSI-deep sea and, figure out where they came from, and their age, and such. But they’re so far out there, they’re not filled with sand from the Columbia River. They’re essentially largely ash falling down or little bits of fossil gunk that comes down. So, essentially these clays are super pure smectite clay. The same clay, type of clay, that they put in your McDonald’s milkshake to make it really smooth. And that’s what it is. It’s really smooth and, when that stuff goes into a fault zone, it’s really slippery. I said, most things have friction like 0.6 or something like that. There are exceptions. Clays are a bit weaker. Serpentine minerals, platy minerals, are often a bit weaker. But these pure smectite clay type-things, generally just weak to start with. So, maybe starting at 0.2. As the rupture comes in, why go through some chert or some basalt, or other things, where I can just kind of glide along? Me being the rupture, I can glide along. There probably are times when ruptures have gone through those other things, but it’s a way, that pathway catching all the way down to the seafloor. That’s kind of a hypothesis, but…

So, where else, might there be large slippery trenches? Well, there’s many big earthquakes all the time, but there’s another big earthquake in this region, the Sanriku earthquake. 1890s or so. We didn’t have seismometers or other things, but people kind of interpreted particularly the tsunami record, that was north of us, almost getting up to Hokkaido. That was probably a shallow earthquake, where there was slip that happened close to the trench, or maybe all the way to the seafloor, as well. So, that’s in this area. But then he can map out where are these clays going down, where they’re not mixed with terrigenous stuff. Where are they? Kamchatka, the Aleutians and other places. That gives us some idea of where we might look for other slip to the trench.

But that’s not to say, though, that you can’t have big shallow slip in other places. So right around this time, of the 2011 earthquake – I’m going to give credit to the people at NanTroSEIZE, whenever they get all this bad, you know, news saying like, “oh, they didn’t get to the plate boundary fault”. I think that that expedition or that whole project was a success in many ways. There’s like two big things that came out of it. And one of them, right around the time of Tohoku, was that, when they were learning with Chikyu how to drill into faults, how to do other things, they went out and drilled across the faults in shallow holes, in the shallow parts of the fault. They learned how to take the fault cores, look at them… Inside of those faults, and inside those cores, they see these slip zones of what are faults. Did they slip in an earthquake, or are they just kind of like creeping along, and they just slowly move past each other? It used to be, 20 years ago, the only way that you could know – well, the only way you can know whether a fault has had an earthquake on it, is to watch and you see that it moved, or you see melted rock on it. It got so hot from that frictional heating, that it melted the rock.

Arito Sakaguchi and others looked at those things and they’re a lot closer to land, they have a lot more terrigenous sediments, they have like little bits of almost pre-coal – almost like coal, but it didn’t fully get into coal yet. They’ve only gotten to, I don’t know what the temperatures are, but not that warm. But then, if you look at it, the shininess of coal can tell you how hot it’s kind of been buried. And they see that, “it’s really shiny, here”. The vitronite reflectance. When they do that, they look at it and they say – people have calibrated these things of this coal for the oil industry, because they want to know where is the gas window or the oil window; where have all the organic materials gotten cooked to. When they see that these materials right in the slip zone have increased by like hundreds of degrees above the surroundings, how do you do that? And it’s only in like a centimeter or less. How do you do that? It’s really hard to get hot water that comes up like hundreds of degrees just in like a centimeter. It’s probably from the frictional heating. But they’re only like a few hundred meters below the seafloor. That meant that in two places, both out near the trench and on this fault, have evidence of large amounts of slip, rapid slip, during earthquakes. So even though we saw shallow slip and such in Tohoku, we thought it was crazy. Here’s evidence that these other faults in Nankai have also had large amounts of slip all the way to the seafloor. So that, I think, is a pretty big result.

BMR: So, it was essentially a new way of understanding big earthquakes; not that much about why a magnitude 9 earthquake happens, but on why it creates such a big tsunami.

PF: Why did it create such a big tsunami and certainly the big point is, does the seafloor jump a lot more than we expect, anticipate? That’s a lot of it. But on an even simpler version, we want to know things about the friction and the brakes on things. And we still don’t fully understand this. Why do some earthquakes only grow to about one size? And why do ones grow to be gigantic? What makes an earthquake start? What makes it stop? Makes it grow to be really big? And it’s not just probably friction, it’s certainly not just clay. There’s a lot of things in there. If we can get some constraint on at least what’s going on, or in one spot during a big event, that just gives us more evidence to try to figure out how the whole thing works all together.

We’re not done, though. That dataset is amazing. The temperature data.

BMR: The dataset you were dreaming about for at least two years.

PF: Yeah. But we had started thinking about this project back in 2007. I said at the beginning of the drilling, it’s really cool from the doing a sort of water circulation in the borehole. It took some time. Some places it took a lot longer to recover than other places. And looking at that, it’s like, “Hum”. Our models say just circulating the water against the rock should take 20 to 30 days to kind of recover. But hmm… Some places took like 60 days. How we interpret it is that there’s some places that have a lot of faults and fractures that are really permeable. So instead of just washing the cold ocean water, touching the rocks and cooling them off, they infiltrate the rocks, cool off a much wider zone. So now, with the profile with depth, we can know see where are the permeable zones. We care about hydrology. Hydrology is kind of my first job, I guess. We care about the hydrology because we care about how fluids are moving around. Are they transferring pressure around, or building up pressure in certain spots, weakening the fault itself? So, we could see – we have not just like a single measurement of the permeability; we have kind of like a cross-section of what does this fault zone look like in terms of hydrology? Main plate boundary fault … really impermeable. That’s why it was not disturbed by temperature, or by fluid flow. And we can still see that temperature anomaly, and it’s not being affected by fluid flow. But we can see where there’s permeable spots elsewhere. But then, we recorded that magnitude 7.3 earthquake. The plate boundary fault did not slip. It happened on a much deeper fault below us. We saw how the whole system responded to that. So, our sensors can measure to 1,000th of a degree Celsius accuracy, resolution even below that. So, just the smallest movement of water, like just shaking up or like flowing through fractures, like wind, you can sense that. We can sense that with our sensors.

In one spot, in this one fracture up above the plate boundary fault, it seems like a low permeability plate boundary fault, and then lots of fractures and they diminish and get further spaced out above it. We kind of thought like a damage zone, a bunch of broken rocks above it – the clay and the broken rocks, mudstone deposits… We see that through this one fracture before the earthquake, there’s kind of like a spring. There’s like water coming through. And we could see that. And it’s kind of a little bit noisy in the temperature data, because it kind of goes up and down, and fluctuates. This spring is kind of neat, fun. Magnitude 7.3 earthquake shook up the whole place. That spring shuts off. Immediately it starts coming out from another one, like 20m above. Another one starts at the same time. So, we could see how the hydrology, the flow network, is changing in the system in response to a big earthquake, a big aftershock after the Tohoku earthquake.

Then, looking at the fine details – I’ve worked with a lot of seismologists, and they like to look at wiggles. Then, I filtered the data and looked at all the wiggles, and I can see there’s, sometimes, especially when we suspect fluid flow going around, the temperatures go up and down, and up and down.

When we plug them all together, it’s kind of like how Obara-san found tremor. It’s like how he put all this data on HighNet [Seismic Network], and we see a bunch of noise over there, and I see a bunch of noise on a lot of sensors. Well, that’s kind of what we saw on the temperature sensors, is that some places there’s a little bit of noise above what we think is instrument noise. And we plot them together, the noise is correlated in different sensors. They are all autonomous. They’re only connected by a rope between them. They all have their own sensors, their own data logger. So why are they being affected? Why are they having the same noise going up at the same time, going down at the same time?

Then some would go up, they would all go up, and then some below a certain depth would all go down. Twisted my brain, for a while. I think it’s fluid flow. So, like the wind. If the wind goes by you, you can feel it on all your sensors, your elbow and your wrist. And so, we have different sensors. If fluid flow is coming through with advection, you can sense it on those sensors. And that’s what we think we see. Why do some go up and down? We think it’s coming out through this mapped fault or fracture. In some places where, because the temperature gradient increases with depth, if it comes out in one spot, and water comes to shallower depth, it’s going to be warmer than the surroundings. But if that same water goes down to deeper depths, it’s going to be coler than the surroundings. So, we see that pattern. And so – I’m giving my talk at this point now, but I stole this idea from the seismologists I work with, that they’re trying to find tremor. Like, “Oh, there’s this math trick where you can just take a window of time, and you can do cross correlation and say, “am I similar to the other one nearby? Am I correlated or not?”. I do that, and squinting my eyes, I can just map where the temperatures are correlated. So, I can just map where fluid advection is happening in space and time.

Now, they are happening in pulses, at certain times. They’re happening at the same times. Boom – of all this; boom – on all these sensors. Those times correspond to aftershocks in the region. They’re all coming out from like certain fractures, particularly this one fault. So, essentially, what’s happening is that this fault –not the plate boundary fault, but these other faults and fractures – are responding to aftershocks, and they’re allowing fluid to flow for like a half a day, a quarter of a day, or several hours; and then, settling back down again. That’s pretty neat.

So if that happened – well, it does happen – on a larger scale, that means that faults can open, they can transmit fluids to another places if they get trapped somewhere; it builds up pressure in some places, and that could cause deformation, cause another earthquake… So, this is kind of a process that people talk about in geology, this process of how at deeper depths, in hotter temperatures, gold appears in veins. But here, we’re seeing it in real life, underground, over time. So, a lot of neat things like that.

BMR: These are the results of JFAST. How they are connected to the current expedition, JTRACK?

PF: We’re here. We learned a lot about how we can study hydrology I think in the years since then. Particularly in Nankai and other places, there’s been a lot of interest in thinking more about hydrology and connections to that. Let’s just go to JTRACK, in general. JFAST was a remarkable success at this, despite all the things we couldn’t do and all the troubles. We logged, cored, and put in an observatory. But all those things, we did in small amounts. Logging, I think we got it; we got the stress conditions and such. But the coring, we essentially just kind of got to the plate boundary fault. We had a few other places and such. But where does this fit in the context? What’s all that stuff going on up above it? How it’s like the whole thing? Were we just lucky? It’s a lot to interpret a whole system on one fault core. So, how does that all set? What are those incoming plates? How much gets scraped off? How much does it all come together? What is the overall structure and architecture of this thing? There are clearly other faults that we do not capture in the core. Do they participate in these big earthquakes? Or do they all just kind of creep? There’s some indication from some of these things, like trying to see the thermal bits, the parts of where the rocks have been cooked. There are some faults that are apparently formerly hot, that they’ve been cooked. So, they’ve had big earthquakes, on them.

Immediately, we knew that we had to come back, to really get a better picture of this. Get the incoming plate, get this side as well. And when we pulled the sensors out, in 2013, we left the hole. There was not really an easy way to get sensors back in, to the hole. So that was it. That was the end of the experiment. We thought we’d come back, hopefully in a couple of years. And so, we wrote a proposal, it went through a lot of work, and maybe we were more like a regular IODP proposal. It took a long time.

BMR: Why did you – the science party – decided that you needed to come back here?

PF: Well, it’s not that you want to go back and do it again. That’s not really what it was about. Really, we wanted to make a bigger picture of it. We had big questions out there. And there’s a reason why it’s called JTRACK: is that we wanted to do transects. We’ve got one spot on the big rupture. One spot by itself, site C0019, this is the spot that had the most amount of slip during the earthquake. Is it related to the things that are coming in? We had a reference site that’s really far to the north, drilled a long time ago, in the DSDP site that we were using as a reference. Is that really what’s going down in this spot? It would be great to have the inputs here, as well to know more about here. But to do a transect here, in the input part and in the trench, wouldn’t it be great to be able to see in the trench what is the history, from paleoseismology? To know what the historic record is. You know some things about the structure of it, the stress conditions, the physical properties of what’s going on here. You know what’s coming in, so we can understand how it’s all kind of being formed, and know the history of earthquakes through the faults that we see in the core, but also in the paleoseismic record. Do it here, on a transect here, track it here, but also to the north, where the Sanriku earthquake happened in the 1800s or so. In Tohoku, it slipped a little bit less there than on this transect. Is there a reason? We think it might be these clays and other things, but we’re like on the top of a horst. Essentially in the uplifted part, there’s normal faults. What happens in the fault down in those parts? What happens to the north? Does it kind of follow along the same thing to the north part of the Tohoku rupture? Does it behave differently because the clays aren’t there, or the geology, the architecture of the faults, and the down-going plate is a little bit different? Let’s go up there.

Also, to the incoming plate, see if it differs, if those clays are there. Also, look at the parallel seismic record into the trench. And then, while we’re at it, why do we go to the south, as well? To the lower part. So, three transects – that’s what we propose. JTRACK is really a big, big project. It’s not just an expedition. And, from that, with time, and workshops, and reviews, and other things, it’s evolved and it’s certainly not over. And so, part of that was, wow, this paleo-seismic part in the trench that seems like a separate thing. We maybe break that off into a separate thing by itself. And, in some ways that has gone. Expedition 386, with which was not with Chikyu, or JR. It was with the [R/V] Kaimei, But essentially, they came out with a ship, and they did giant piston cores to get the seismic record there.

And there is an APL [Ancillary Project] that’s approved; may sail next year, to go back with Chikyu, to go even deeper in the trench. But that’s all part of the general JTRACK idea. So, we’ve got inputs, and we’ve got that JFAST and JTRACK site here, at [site] C0019 really well characterized with almost two dozen holes around in this area, or so. This is the inside part of the trench.

But then, with time as it came on, 12 years later when we finally get out here, some of our understanding of these things and some of our questions evolved. Including, 12 years later – it was one thing that maybe part of it was put an observatory in there, so that we could perhaps see, with pore pressure, how the fault would be building up stress or starting to heal after the earthquake. Now, 12 years later, it’s like, has it healed? And so, what are the stress conditions? Some of the things about building a pore pressure observatory, I think we’ve learned from some places they’re really awesome. That’s the second big success of NanTroSEIZE. Having these – I think – three big observatories that are measuring pressure, you can see how slow slip events come through, like ten times more sensitive than these networks and arrays of ocean bottom pressure sensors. And you can see when they’re happening, when the ocean bottom seismometers don’t really see that they’re happening; or you start to see that they’re happening hours and days before you see them on other things. Amazing.

But we also learned how difficult, particularly at Hikurangi and in other places, how difficult it is to put in these straws and other things. And so, pressure and then, essentially, you get some idea about the pressure, or the hydrology at one depth. But I think people recognized that we can learn a lot beyond just temperature. You can learn a lot about the hydrology from these temperature arrays. So, that’s where the idea for the JTRACK one came about, to go deeper than we went before. To go much deeper all the way into the cherts down below; make sure that we’re crossing any of the faults that may be active, along the way, and prism, and in the plate boundary.

BMR: Now there’s another observatory waiting for you to install.

PF: Yeah.

BMR: What are the differences between that first observatory and this one. What things have you improved? What things are new, to test?

PF: When JTRACK was approved, it’s like, “Okay, let’s do an observatory”. Do we want to do pressure? We had a task force of observatory scientists and people with experience, to come together and say, “What are our objectives? What are the things we want to learn? How do we do this?”. And, you know, observatories are complex. Also, by the time that you might get approved for something like this, it starts the clock. And that means you’ve got to find funding for the observatory, you got to get it built, you got to make it work. Even though we had more time like this, essentially, we were on the clock. Kind of like with JFAST. We certainly had more time, but not a lot of time to put something together, get funding for it, and such.

So, I think that the consensus was, again, let’s focus on temperature, not on pressure. But there are certainly changes, in the past 12 years. We’ve learned a lot about what we could do with these types of things, from the success of JFAST, and continue looking at that data set. But there’s also challenges. Kaiko (ROV) can’t go to these depths again. If we put in an observatory, how are we going to get the data back? There was a lot of discussion about how do we build something so that we can get the data back?

BMR: Is there any submersible in the US or in any other country, that can go to these depths, these days?

PF: No… Shinkai 6500 goes to 6500m depth. Not quite there. I think there’s a lot of work on AUV and some other things that can go to these depths. There may be some other things that can go down there to deeper depths, but not ones that can really manipulate things. You know, James Cameron went down in his little submersible to like 14km depth. But that thing does not – pretty much it just sinks and goes back up. And so, you can’t really, do much otherwise. So, there’s not something kind of available. I didn’t really know until just a few years ago, perhaps, that submarines, like naval submarines and stuff like that, they don’t go to almost anything in terms of depth. I thought they were going down in the trenches. They are like up in the wash, pretty much.

Then we looked and we talked a lot with JAMSTEC and said, okay, so what’s possible? We’ve talked a lot to oceanographic instrument manufacturers and thinking about underwater acoustic modems, so that if we can get to something that could go to deep depths, maybe you can transmit data or transmit data in the whole water column. Risky. Unproven. Totally experimental. It’s not what you want to do.

You approached manufacturers. What kind of companies are those? I assume they are working for offshore industries; so how did they react, when you approached with these high-risk, cutting-edge instruments for science?

PF: Some would not answer my calls, and some maybe I don’t want to answer their calls (all laugh). But there’s one that I work with a lot: RBR, in Canada. They’re not an oil and gas company. They make instruments for oceanographic research, and they’ve been involved in IODP and ODP-type things for a long time, particularly with observatories and other tools that we use in ocean science. They’ve been good partners in this. With JFAST, we were able to use some of their sensors that they put on moorings. That’s why they already make ones that go to a thousandth of a degree. They’re pretty wide diameter, we’re trying to get into a small hole, I prefer them to be smaller. And they said, “well, you know, if you buy a lot of them, we can redesign them”. They just went ahead and redesigned them to the diameter that we wanted. And so, since JFAST, they’ve made them better. We had lots and lots of these sensors. They’re very simple, compared to some of the other things. They make CTDs, conductivity sensors, temperature, depth profilers, and things. But they’ve been a good partner.

BMR: Who put the money for the observatory, this time? And maybe you want to mention also how much an observatory costs.

PF: I just don’t really know. It sets them apart. There are different parts to it. And this is part of the beauty, perhaps, of IODP or of scientific ocean drilling. A lot of the stuff, you get awarded. I think we appreciate it. When I tried to tell this to my dean at my university, like, “This is big deal”. They usually think about, “Well, how much is it?” Even if they’re not getting the overhead from it. But this is a big deal. But a lot of that is kind of absorbed and you, as a scientist, don’t have to worry about the budget. You worry about the science; for co-chiefs, you worry about the staffing of the other scientists, and you think about the science objectives, you focus on that. So, that’s the beauty. I’ve been involved in other drilling projects on land, where you have to find all the contractors, and you have to make your own data management protocol, and you have to find your techs, you have to find the driller, you have to find all the service things. Yeah. Not fun.

But, for the observatories, they’re considered third party. So, they’re not included in the general package of getting an expedition. Though you can use your drilling time to do it. And there’s engineers, often, to help you do it, to do the science. But for the instrumentation, you have to get that yourself. So, usually how it breaks down is like the steel, like the casing, the wellhead, big parts, all the things that are kind of standard fare for drilling and wellbore, that’s within the IODP part. We have to worry about the instrumentation, whether it’s straws on the outside, and pressure loggers for pressure CORKs; or, in this case, sensors on a string. We deal with that. So, it depends. Sometimes we have to deal with the rope and usually the sinker bar; and, in this case, the rope was part of the package. We just had to worry about the instruments.

So, this time around, by the time we were really approved, we pretty much had only a year and a half before coming out here. And we were still, again, not certain how we were going to build this observatory, because we didn’t know if we could get the sensors back. So, we had a longer heads up on this one, but we were still kind of in a similar position with JFAST. It’s like, “Okay, how are we going to do this? And how are we going to design it? And then how are we going to get funding for it?”. In the end, most of the sensors – we have 186 sensors; JFAST, 55 sensors – huge amount. Most ever we’ve really put in. Some of the things that Andy Fisher, Keir Becker did in holes for hydrology in ocean crust – 10, 12, 14? And that’s perfectly great for what they want to do. With 55, particularly finely spaced ones, we could see these transient advection signals. We could really kind of map a lot of things really nicely. Wasn’t that awesome?

Let’s go more. Let’s not just focus on the plate boundary. Let’s get a large profile. So, we want to propose a deeper borehole, and sensors all throughout the whole thing. So, that’s a lot of them. In the end, most of them are paid for by internal funds, essentially startup funds, that I had originally had. So, we use our own funds to moving things around. I gave up a postdoc that I was supposed to have, you know, funding that had for a postdoc, to buy a bunch of sensors. It’s an investment. We’re going to get awesome science. And with that, hopefully, we can go to NSF and say, “hey, we haven’t knocked on your door yet”. For JFAST, analysis was paid for by the Gordon and Betty Moore Foundation. And NSF certainly supported us through their participation in IODP, and through the US Science Support Office for IODP. With JTRACK, too, US Science Support Office in the end, at the very end, right before we came, gave us funds for 27 sensors. And that’s largely because, in addition to that big one observatory, the deep one that’s part of the regular program, we found a way to get the sensors in and out. And the way that it is, is that we decided that, again, we want to go more sensors rather than a modem, or something like that. Modem, risky, and things never really been done. And then with a modem or something where, again, you have one data logger at the surface, you’re limited on the number of sensors that you’re down below. 12, 24. We’re like, we want like high resolution, spatial resolution, to capture all these things in this almost kilometer below here, this whole prism structure. So, we prefer to go for more, which meant that we’d be, again, risk of getting caught and stuck down there, and not as easy to get them in and out; but let’s get them in there, and we’ll think about how we get them out of there.

But we came up with a way to get them out and, extending Kaiko to seven kilometers, again, outrageously expensive. Essentially, it just needs new cable. Outrageously expensive. That’s not going to do it. The answer is, the thing that can do impossible things. The only thing that can do impossible things in here, it’s Chikyu. Chikyu can operate in these water depths. If we can get the sensors in with Chikyu. If we can go back with Chikyu, you create like an upside down funnel, grab on to the well again, we can perhaps pull the sensors up through the drill string, just like we pull the core barrel up through it. So, that’s what we thought. So, over the past year, folks at JAMSTEC created this re-engagement tool, essentially an upside down funnel that can connect on to a wellhead. So if we put them in there, it can go back to our wellhead and we can connect to it. You can go down with the core line winch, and you can fake out, tell the core-liner winch: go get that core barrel for us, and grab on to it and – oh! fake out. You’re pulling out our observatory string.

So now we’ve got a way to reengage with a wellhead so you can take sensors out. Well, could you put them back in? Sure. You can put them back in. Well, hey guys, any chance we can go back to that JFAST well site? That’s not part of the expedition. We didn’t approve that.

In IODP, if there’s an expedition that’s already granted, you can write a proposal, an ancillary project letter that says, “Hey, you guys are going out there, but I’ve got some cool ideas while you’re out there, to do something”. And if it gets approved, they will give you some time on that expedition to do that extra ancillary science part. Generally, how it’s been like on the JR, you get your project approved and you don’t even think about it. You’re just like crossing your fingers that no one puts in an APL letter in (laughs), because essentially, they’re stealing time away from it. So when this came about, it’s like, “we’ve got a new way to engage a borehole”. Wouldn’t it be great to go back to JFAST? Where we see these faults that respond to aftershocks. Are those same faults active? Great, we’ll have a new one (observatory), but are those same ones (faults and fractures) that were behaving hydrologically weird before? Are they still doing that now, 12 years later? Wouldn’t it be great to go and see? So, I said, “Is it kind of rude or kind of shitty to write an APL to your own expedition?” (laughs). My co-chiefs, my co-proponents of this project, I was like, they’re going to hate me (laughs). I said it kind of jokingly because I was like, “oh yeah, I’m not going to do that”.

BMR: You just hosted a tiny hope that it could happen.

PF: I just kind of put it out there, and the feedback I got from the engineers was – maybe they were supposed to be kind of indifferent, but they were like, “Yeah, that’s pretty cool. You should do it”. Because on Chikyu it works differently. An APL, instead of taking time away, if you really can advertise or like really advocate that you’ve got something really cool, a cool add-on that can do, expand – you know, you’re already out there, putting more investment in there – more bang for your buck. They can potentially, under consideration at the Chikyu Board (CIB, Chikyu IODP Board), they can consider adding time to the expedition. So, that’s what we did. And instead of my geologist colleagues, co-chiefs – I think they all liked it –, but Jamie (Kirkpatrick) said, “Yeah, that is cool. We should do it”. So Jamie kind of joined me in that, and he said, I think I can get some sensors, to add to this part.

The other part about it, though, and thinking it through of building off of mistakes, maybe not a real mistake, or things that you learn through stuff, when they put in an observatory in Nankai, they already had observatories there. They had an observatory at one spot. And actually, they weren’t building another one. They had an observatory at one spot, and then they were drilling some other places nearby. They’re drilling nearby, and they’re measuring pressure. When they start drilling, the pressure builds up like – urgh, you’re screwing up our data set! And they drilled another one – pressure builds up. It’s because when you drill the hole, you’re circulating water, and it’s under pressure to get all the rock chips out. So that pressure, even though they are like 30 or 50 meters away or so, that pressure is kind of percolating or diffusing through the rock, until it hits their pressure sensor over here. They were smart, and they said, “Oh, well, we know when we started drilling over here that there’s a time delay”. And so that actually gives us a measure, the time delay from when we’re drilling over here and we’re circulating that pressure, it’s diffusing out here and takes some time to get over here. That gives us a measure of the hydraulic properties of the subsurface at a large scale, not unlike a little sample that we often get – we get a little sample, put it in the lab… Or, on a sample size of measuring around the borehole. It’s a very large scale, measure of it. Super cool. So, I said, “Oh! We’re going to be doing a lot of holes at JTRACK. Wouldn’t it be great if we could go back into JFAST and see if we see something?” But we’re not measuring pressure. So, we had to think it through. Our models suggested that this is the case. When we are doing pressure over here, the pressure front will still come and hit JFAST. We’re not measuring pressure. But, again, with temperature – what can you do with temperature? But when the pressure front hits the borehole, it causes fluid flow, when it hits the borehole. So you’ll see that in the advection of the water moving up and down at the sides of the borehole, just like we saw the signal when fluid hit / came in after those earthquakes. So, I think that we can see a thermal signature, not of the cold water that comes through – it will warm up by the time and be in equilibrium – but when it starts to cause flow around the borehole, we should be able to see that. And we’ll see. We’ve drilled a lot of holes around here, and not only can you just do it for one thing. We’ve got like, not necessarily 360, but we’ve got like a whole arc of boreholes around us.

So, at the beginning of JTRACK, we got approved to be the first thing. And that’s why it was that the first thing, to put the sensors in, to see if you can see and sense all the other drilling that’s going on around here. Large scale hydrology.

BMR: At some point you talked about gathering support to buy the sensors. Well, first to move forward this APL. How do manage to get support for this kind of APL? Have you encounter some sort of reticence to get support?

PF: Not necessarily reticence. I think there are challenges. Challenges with just the funding system of NSF, or something like that. It pretty much takes like a year or something like that. So, if you’re lucky to get an NSF grant, you have to spend a lot of time writing one major competitive one. It goes through a process, so it’s at least like six months, at minimum, to hear back. And then, there’s some time to actually get the funds in place and everything. For these types of sensors, we need to give them like 3 or 4 months’ notice, to be able to order them, pay for them, and then get them. And then, get them into the country. This takes another six months, as well. So, pretty much by the time that we were approved with the expeditions, it’s like we’re already cut short. We had to find other funding strategies. So that’s why it was largely out of our own funds that we did this.

Then, when the APL came and we were like, “Oh, we’ve got this idea and we got that approved”, it was like – well, we were aiming for like 200 sensors in just JTRACK, and we didn’t really get there. I think we’re going to have 128. But with that, it was like, “but now we’ve got this other hole that we also want to put sensors in”, with the APL, to do this other experiment. So, we took some from the JTRACK ones, but still, we didn’t want to take too many from it. So, we talked to US Science Support Office for IODP, and they were able to fund us to get 27 more. That really made it work.

I think that there is support for us. I think there’s just challenges with how it all works. Part of this was, at the beginning, like, “Okay, we got a thing going. We want to do an observatory”. We just called the community. The IODP community, the Ocean Drilling Community… It’s pretty supportive, generally, and it’s pretty much a team effort for all these things. You don’t really go out on any of these expeditions as a solo scientist. There is a lot of people involved. So, we called everyone up and we said, “Hey, let’s just meet”. And we had this big meeting, and we went back and forth on BaseCamp and, just said, “What are the pros and cons on these things? Do you have any advice? Should we just do what we did the last time?” Simple, easy, off the shelf, ropes and strings. Or, do we build one like most other observatories are? Most other observatories are these pressure sensors or these pressurized ones. These CORKS, with straws and pressure sensors. Or do we do some hybrid thing? Or do we do something with acoustic modems? We explored all those options. Surprisingly to me, it seemed, from more experienced people at observatories than me, they said, “do what you did for JFAST”. That was reassuring.

BMR: What would be your next target? The APL has already some sensors in, you are getting ready to set a new observatory; let’s assume that everything goes well and you retrieve both strings in some time. What would be your next target, in terms of science, in terms of geographic scope?

PF: I think the next big objective is to get other people, to get younger folks, into this. Huiyun Guo, she’s the next generation out of these things. Get other people to think up their own ideas, and I’m happy to help. But there are other ways, and I think moving away from the things that we, or how we did in the past, great. Don’t be restricted by the way that we’ve done it in the past. Not doing straws – and they hate it when I call it straws – the straws to pressure sensors, and measuring pressure at one depth. They are also, particularly for slow-slip events, amazing. But we can do different things with the temperature. Maybe there’s other stuff that can be done. I think we benefited a lot in terms of general understanding, where I think the real societal impact of observatories, the stuff that they’re doing with monitoring slow slip events out there, is so amazing… But it’s best done, we are doing it in some lesser degree, to some degree, in Hikurangi, as well in New Zealand. But all these, we could see these transient processes, how the faults are evolving, how they’re moving or doing something else. It’s cool, but I want to know that it’s cool not when we went after an earthquake and said, “oh yeah, it was doing something beforehand”. I want to know it now, that, “Oh, the fault is doing something, is behaving weird”. I want to know it now, to be able to tell people about it. And that means that we got to figure out how do we get power out there, and how do we get the data back. So, in Nankai, they are connected to fiber optic cables, now. And that took a lot of investment and other things. And it’s only got three spots, now. I think there’s work now on putting similar observatories elsewhere, in Nankai.

But I think that those type of things are one aspect of subseafloor observatories, that I think that there’s huge societal potential, though outrageously expensive. Millions of dollars to build these observatories. You asked me how much they cost. They are million dollars. That’s on top of going out there with a drill rig and other things. There are a lot of money. And so, you put all your investment in that, or do you put it on AUVs and other things? For slow slip, they’re (observatories) ten times more powerful in terms of resolution. You can see things that you can’t see with ocean bottom pressure. Yeah, it’s hard. But, you know, there’s so much going on underneath the oceans, and in these faults that have these magnitude 8 or 9 earthquakes, that we just can’t see because we’re not out there looking. Or we can’t look out there. GPS doesn’t work underwater, or we just don’t have instruments that could go there. Or, we have the potential to actually get them underground and see what’s going on inside of some of these places. So, those are things.

There are big science questions about hydrology and other things that I’m interested in, as well. I think it’d be really cool. I’m personally involved in a project, an idea for drilling in Hyuga-Nada, where there’s this down going seamount. There’s a lot of tricky bits with that, but with observatories, there’s other ways that you could  measure a lot of things with fiber optic cables. Instead of putting all the instruments down where it might be hot – shoot a laser beam into fiber optic cable. Backscatter light can tell you things about strain, just the cable itself can act like a geophone array. You can measure temperature not nearly as high resolution as we can do with our sensors, but you can monitor this stuff over time. So, those things are pretty neat. Putting actual seismometers down in these depths, and listening a little bit closer. But seismometers require a lot of power. I’m using a little double A lithium battery or something like that. And it can last like seven years. You can’t really do that on borehole seismometers, get them in and out. There’s a lot to be done. We just we need to bring more people in, and be excited to know how to do these things.

But there’s also potential because we do one of these things maybe once every five, ten years or so. But there’s a lot we can do on land, as well. The stuff that we’ve learned from JFAST, and other observatories and things, we’re bringing it back to land. We’ve learned a lot from oil and gas industry work. We’re bringing it back. Or bring it to geothermal energy. We’re trying to figure out where permeable faults and fractures are, how are they evolving as you are doing operations; are they opening up? it’s a lot hotter; we have to use different instruments, often times. But those types of things are where I see a future for.

BMR: We’ve gone through all this story, from JFAST to JTRACK, which is very tied to your career path. What’s one thing that you’d like the early career who are now participating on JTRACK learn about these stories? One takeaway message.

PF: One takeaway message is something that I’ve learned before JFAST. I went to a workshop for early career scientists on how to write an IODP proposal. They talked to us and told as – we kind of even believed them – and they said, “You, too, can form an expedition. You can have your own project. They take like ten or fifteen years to go, so start to think about it now” (laughs). And we’re like, “oh great”. But the main thing was networking. You see all these other people. I didn’t really think it was going to happen. But I think that that’s the thing to think about.

The take home message is that, scientific drilling – and this is why some of my mentors, I didn’t fully understand it at the time. I knew that they were involved in, really enjoyed the community of it – they said, “you should get involved in scientific ocean drilling”. IODP at that time. Is that you can do big things. You have a huge community. These projects and the science that we do is bigger than any one person. You can do big projects. You can be directly involved and do big things in it. And you can help drive it, and you can come up with impossible projects or missions. And there’s this whole community that is supportive and will – some of it may be really impossible – but they will drive you to what is possible, within the limits. It’s very supportive, in that way. It may take a long time, to do some of the things, but you learn along the way, and you start maybe going and doing something as you’re involved in it, and finding things or becoming involved in things that you didn’t even think about.

I think that there is a lot of room for leadership and for creativity. I hope that scientific drilling, whatever the form it is in the future, remains in that way. And I think that that’s the main thing. We lost the JR, you know, it’s going to retire, I think the main thing is less about the ship. It’s more about the community, and the potential. We’ll all know each other otherwise. But it’s really about the potential and possibilities of the things that we can do, the science that we can do.

BMR: That’s a great message. Well, thank you very much.

PF: Thank you.