Takeru Yoshimoto

Disclaimer

This transcript is based on a video-recorded interview deposited at MarE3, JAMSTEC (Yokosuka, Japan).

The transcripts of the research project Oral Histories of Scientific Ocean Drilling are polished representations of oral conversations, and are intended solely for the purpose of preserving and documenting personal accounts and memories. They are not a literary product, and are not intended to exhibit literary qualities.

The primary goal of this transcript is to capture the spoken words and memories of the interviewee as accurately as possible. Minor editing and polishing works have been performed to enhance clarity and readability while maintaining the authenticity of spoken discourse, including non-standard grammar, inconsistencies, repetitions, and pauses. The interviewee has been allowed to review and edit the transcript, and they have approved the publication of this version before posting it.

The reader must be aware that memories of an event can vary between individuals and may evolve over time due to various factors, such as subsequent experiences, interactions with others, and personal emotions.

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Please cite the interview as:

Interview of Takeru Yoshimoto by Beatriz Martinez-Rius on 2024 September 16, D/V Chikyu (Japan). [link]

Beatriz Martinez-Rius (BMR): This is Beatriz Martinez-Rius, postdoc at JAMSTEC. I’m with Takeru Yoshimoto, thank you. Can you please introduce yourself?

Takeru Yoshimoto (TK): I’m Takeru Yoshimoto, and I’m a PhD student of Kobe University.

BMR: In which year of PhD are you?

TY: I’m a first year PhD.

BMR: So this is your first year, and you are already starting with an expedition.

TY: Yeah, from April.

BMR: Wow! So, will your PhD research be based on this expedition?

TY: Yes. This is part of my PhD thesis.

BMR: So, Takeru, where are you from in Japan?

TY: I’m from Odawara city, in the western side of Kanagawa prefecture. Odawara has a beautiful ocean and mountains, in particular the Hakone volcano.

BMR: Why did you decided to go to Kobe University?

TY: I’m interested in Earth sciences. When I was 17 years old, I had to determine the department of university I wanted to attend, and I found Kobe University and planet sciences. So, to keep my motivation to study a lot, I chose a university far from my home (laughs). I wanted to live alone, yeah. (laughs)

I was interested in stone pebbles since my childhood. So, this was my first impression of Earth sciences.  Odawara city has an interesting geological setting, and… I only noticed it when I entered at Kobe University, but it is actually a very original setting. That’s why there are various types of beautiful stones near the ocean. So, I enjoyed collecting stones.

Takeru and other scientists examining cores onboard Chikyu, during IODP Expedition 405. ©️Doriane Letexier / JAMSTEC / IODP

BMR: And how did you go from pebble stones to paleomagnetism?

TY: Actually, I’m now interested in structural geology, like fault zones or metamorphism. And the paleomagnetic studies are kind of part of the work to understand the tectonics.

BMR: Was there any scientist in your family? Or someone who was influential for you?

TY: Not actually, but my father was an artist of glass. So, when I was a child, he had huge plastics with sands, and he blew them to make glass. I collected part of the glasses. So, that’s maybe part of the reason I was interested in the Earth and in stones.

BMR: That’s really interesting. So, how did you know about scientific ocean drilling?

TY: I knew about scientific ocean drilling via the classes, when I was an undergrad student. And, at first, I was so surprised… to be able to drill so deep, it was very exciting for me. Then, when I was a master course student, one of the Expedition (405) co-chiefs, (Shuichi) Kodaira-san, made a presentation about J-FAST and J-TRACK, about the Japan trench, at the Japan Geological Society annual meeting. After that, I decided to apply for this expedition.

BMR: So, you started your PhD and applied to J-Track. What motivated you about this expedition?

TY: My biggest motivation is – I was so shocked during the big Tohoku earthquake of 2011… I was 11 years old, actually. In Odawara we had a big earthquake, too. I hoped, or wished, that as many people as possible survive to this kind of earthquakes. So, to prevent earthquake-related disasters is my biggest motivation since childhood.

BMR: I think that many Japanese people share this motivation. So, why do you think you were selected for being onboard Chikyu?

TY: I don’t know the reason (laughs). But, yeah, I’m so grateful…

BMR: What kind of things did you wrote in your application?

TY: I have the scientific plan to reproduce the décollement zone that generates earthquakes. To reproduce the décollement zone, we need samples from the décollement and samples from the proto- décollement. And these sediments in the proto- décollement, will become the décollement or will be the plate boundary fault zone. So, this is one of the reasons to apply.

BMR: This is your first time offshore, if I understood it correctly.

TY: Yes.

BMR: How is it going so far, these first couple of weeks?

TY: It is exciting, because we can only see ocean around us. I feel like… Not alone, but kind of sad? But when I saw the fish in the ocean I felt that, “Oh, we are not alone!”. Yes, it’s so exciting. We always see another ship around us, so it’s not… that sad, for me.

BMR: Not so lonely, you mean?

TY: Yeah, not so lonely. And I really enjoy conversations with friends, playing ping pong… And thinks like that.

BMR: Tell me one thing that has impressed you about Chikyu or about the project we are doing.

TY: One of the biggest impressions is the size of the ship, and the size of the project. So many people are working here to drill and get cores from the bottom of the ocean. I’m so interested in that.

BMR: How about the international collaboration? I imagine this is the first time that you are with such a group from different countries. How do you feel about it?

TY: Sometimes I feel some difficulties to communicate with each other, but I want to talk with my friends. One of the good points is that we can communicate with various scientists – sedimentologists, structural geologists… It’s a very special experience, for me. I’m very glad to be here.

BMR: Where do you see yourself in ten years from now?

TY: After getting my PhD, maybe I continue research as a researcher or in another position. One of my plans is to work in an institute to prevent disasters, to work for natural disasters prevention. So, I will apply my studies to prevent earthquakes disasters.

BMR: I really hope that you achieve it! Thank you very much.

TY: Thank you.

Takeru having fun up at the top of Chikyu’s derrick. Photo by Beatriz Martinez-Rius.