Field trip to Noto Peninsula
I visited Noto Peninsula in central Japan, where M7.6 earthquake occurred on 1 Jan 2024. I saw the great uplift on the western coast and surface rupture in the eastern area.
Welcome to Yasunori Sawaki’s homepage!
My name is Yasunori Sawaki (Ph.D., he/him), an assistant professor at Ritsumeikan University, Japan. I am an early-career researcher in seismology (a study of earthquakes and interior strucure of the Earth), who earned a Ph.D. (Science) from Kyoto University (in Japan) in March 2023. My current work is to estimate the detailed geometry of crustal faults and the seismological heterogeneity in crusts and subducting slabs, with the aim of advancing our understanding of seismotectonics.
Download the latest CV (last updated on 02 July 2025)
Major papers:
- Sawaki, Y., Y. Ito, K. Ohta, T. Shibutani, and T. Iwata (2021). Seismological structures on bimodal distribution of deep tectonic tremor. Geophysical Research Letters, 48, e2020GL092183. doi: 10.1029/2020GL092183 (Open Access)
- Sawaki, Y., T. Shiina, K. Sagae, Y. Sato, H. Horikawa, A. Miyakawa, K. Imanishi, and T. Uchide (2025). Fault Geometries of the 2024 Mw 7.5 Noto Peninsula Earthquake from Hypocenter-Based Hierarchical Clustering of Point-Cloud Normal Vectors. Journal of Geophysical Research: Solid Earth, 130(4), e2024JB030233. doi: 10.1029/2024JB030233 (Open Access)
- Sawaki, Y., Y. Yamashita, S. Ohyanagi, E. S. M. Garcia, A. Ito, H. Sugioka, T. Takahashi, M. Shinohara, and Y. Ito (2023). Seafloor depth controls seismograph orientation uncertainty. Geophysical Journal International, 232(2), 1376–1392, doi: 10.1093/gji/ggac397 (Open Access)
Upcoming Schedule
| Period | Place | Event |
|---|---|---|
| 15–19 Dec 2025 | New Orleans, LA | AGU25 |
Recent News & Posts
2024 SSJ Fall Meeting at Niigata
I participated in the 2024 Seismological Society of Japan (SSJ) Fall Meeting , held at the Toki Messe in Niigata City, JP, from Oct. 21 to 23. I made a following oral presentation.
- S22-03 “Fault Geometries of the 2024 Mw 7.5 Noto Peninsula Earthquake from Hypocenter-Based Hierarchical Clustering” Sawaki et al.
Our New Paper Published!
Deep plutonic bodies over low-frequency earthquakes revealed from receiver-side Green's functions
We imaged the slab and crustal structure of the Kii Peninsula in the Nankai subduction zone in SW Japan using a receiver-function-like analysis. Positive impedance contrasts in the forearc crust correspond to the top surface or inside Kumano pluton, which may control fluid conditions around slow-earthquake sources.
Check it out below!
- Sawaki, Y., Y. Ito, E. S. M. Garcia, A. Miyakawa, and T. Shibutani (2024). Deep plutonic bodies over low-frequency earthquakes revealed from receiver-side Green’s functions. Tectonophysics, 892, 230536. doi: 10.1016/j.tecto.2024.230536 (Open Access)
JpGU2024
I participated in the Japan Geoscience Union (JpGU) Meeting 2024 , held at the Makuhari Messe in Chiba, JP, from May 26 to 31. I made two presentations: one for oral and the other for poster.
- [SCG50-02] Multiscale Fault Estimation in California and Oklahoma. Sawaki, Y., D. Shelly, T. Uchide, K. Sagae, T. Shiina, Y. Sato, and H. Horikawa
- [U15-P09] Fault geometries of the 2024 Noto Peninsula earthquake estimated by hypocenter clustering. Sawaki, Y., T. Uchide, T. Shiina, K. Sagae, H. Horikawa, and K. Imanishi
New preprint alert!
Deep Plutonic Bodies Over Low-Frequency Earthquakes Revealed from Receiver-Side Green's Functions
We have a new preprint on the seismic structure beneath the Kii Peninsula, southwestern Japan, available on SSRN. While it’s not yet peer-reviewed, feel free to check it out if you’re interested!
Sawaki, Y., Y. Ito, E. S. M. Garcia, A. Miyakawa, and T. Shibutani. Deep Plutonic Bodies Over Low-Frequency Earthquakes Revealed from Receiver-Side Green’s Functions. Available at SSRN: http://dx.doi.org/10.2139/ssrn.4793654
SF-A03 Group Workshop at Toyama
SF-A03 Group Workshop at Toyama was held from Feb. 08–10, 2024. I gave a talk about “Hypocenter-based Visualization of Multiscale Earthquake Faults”.
The presentations on geology related to the mechanism of tectonic tremors were interesting to me. As a research collaborator of group A03, I would like to contribute to the comparative subduction zone studies of Slow-to-Fast earthquakes!
Happy New Year!
Happy New Year! I hope you all have a great year!
AGU Fall Meeting 2023 at San Francisco
I participated in the AGU Fall Meeting 2023 held at San Francisco during December 11–15. We had a good poster presentation with lively discussions with worldwide researchers. I can’t wait the next opportunity to interact with you all!
Visiting U.S. Geologocal Survey in Colorado
I visited the United States Geological Survey in Golden, CO for a month and conducted collaborative studies with Dr. David Shelly. It was a fantastic stay and a good opportunity to proceed my research.
I’m going to San Francisco for the upcoming meeting of American Geophysical Union. I have a poster presentation related to my current study .
New co-authored paper published!
Our new paper is publishded! We analyzed shear wave splitting from receiver functions in Shikoku Island, SW Japan, and along-dip variation of fast axes is clarified. Check it out!
Ruan, Yihuan, Yoshihiro Ito, and Yasunori Sawaki, (2023). Anisotropic Velocity Structure Beneath Shikoku, Japan: Insights From Receiver Function and Shear Wave Splitting Analyses Journal of Geophysical Research: Solid Earth, 128, e2023JB027178. doi: 10.1029/2023JB027178