Researcher Information

OHZONO Mako

Associate Professor

Study of earthquakes and volocanic activities by geodetic approach

Institute of Seismology and Volcanology, Seismological Observation

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Theme

Understanding and modeling of seismological and volcanological phenomena and their mechanisms by crustal deformation analysis obtained from geodetic data such as GNSS.

FieldGeodesy, Seismology, Volcanology, Geophysics
KeywordCrustal deformation, Earthquakes, Volocanoes, Modeling

Introduction of Research

Using geodetic data, especially GPS (GNSS, Global Navigation Satellite System), I measure precise crustal deformation in and around Japan. Analyzing this data, I am trying to understand the mechanism of seismological and volcanological phenomena.
I have studied about estimation of the plate motion and uplift induced by the post-glacial rebound in Antarctica, evaluation of fault coupling status on active faults in inland Japan, modeling of coseismic and postseismic deformation and its mechanism assuming heterogeneous rheological subsurface structure, crustal deformation monitoring around active volcanoes, and so on.
Now I am interested in the relationship between slow slip event and seismic activity in inland, the effect of postseismic phenomenon after the 2011 Tohoku-oki earthquake in wide area including Asian continent, crustal deformation around eastern Hokkaido, and the status of crustal deformation field around the Kurile Trench, where will be generate large interpolate earthquake in the future.
I often go field work to obtain original geodetic data to investigate detailed crustal deformation. GNSS observation network in northern Hokkaido is for slow slip event detection, and eastern Hokkaido for monitoring volcanic activity will give me new knowledges. International research collaboration is also important for me. I sometimes go to Nepal to construct GNSS observation network and Kamchatka for volcano research.

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GNSS observation around Kussharo caldera, eastern Hokkaido.
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GNSS site construction in Nepal.

Representative Achievements

Ohzono, M., H. Takahashi, C. Ito, Spatiotemporal crustal strain distribution around the Ishikari-Teichi-Toen fault zone estimated from Global Navigation Satellite System data, Earth Planets Space, 71:50, 2019
Ohzono, M., H. Takahashi, and M. Ichiyanagi, An intra-plate slow earthquake observed by a dense GPS network in Hokkaido, northernmost Japan, Geophys. J. Int., 200(1), 144-148, 2015.
Ohzono, M., Y. Yabe, T. Iinuma, Y. Ohta, S. Miura, K. Tachibana, S. Sato, and T. Demachi, Strain anomalies induced by the 2011 Tohoku Earthquake (Mw9.0) as observed by a dense GPS network in northeastern Japan, Earth Planets Space, 64 (12), 1231-1238, 2012.
Ohzono, M., Y. Ohta, T. Iinuma, S. Miura, and J. Muto, Geodetic evidence of viscoelastic relaxation after the 2008 Iwate-Miyagi Nairiku earthquake, Earth Planets Space, 64, 759-764, 2012.
Ohzono, M., T. Sagiya, K. hirahara, M. Hashimoto, A. Takeuchi, Y. Hoso, Y. Wada, F. Ohya, and R. Doke, Strain accumulation process around the Atotsugawa fault system in the Niigata-Kobe Tectonic Zone, central Japan, Geophys. J. Int., 184(3), 977-990, 2011.
Academic degreeDoctor of Science
Self Introduction

My original home town is Kagoshima, but I have lived in Shikoku, Tokai and Tohoku regions so far. My hobby is seeing GEONET sites and taking photographs. I like finding and trying something new through field works.

Academic background2004 Faculty of Science, Kochi University (B.S.)
2006 Graduate School of Environment, Nagoya University (M.S.)
2011 Graduate School of Science, Tohoku University (Sc.D.)
2011-2013 Researcher, Faculty of Science, Hokkaido University
2013-2016 Lecturer, Faculty of Science, Yamagata University
2016-2019 Lecturer, Faculty of Science, Hokkaido University
2019- Current
Affiliated academic societyGeodetic society of Japan, Seismological Society of Japan, Volcanological Society of Japan, American Geophysical Union
Room addressScience Building 4 4-203

Institute of Seismology and Volcanology, Seismological Observation

OHZONO Mako

Associate Professor

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Please tell us your stories until you became a researcher.

When I was a doctoral course student, I gave up, dropped out of the university, and I got a job. However, I started wanting to study again, so I re-entered graduate school. It took more time to get my Ph.D., but I managed to get through because it was what I decided on my own after I re-entered. In the month of finishing the doctoral course, the 2011 off the Pacific coast of Tohoku Earthquake occurred. The following month, I became a post-doc and started my life as a researcher. I will never forget that time.

GNSS observation at around Kussharo caldera. To grasp the detailed crustal deformation, dense GNSS observation has been carried out.
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What is the research theme that you are currently focusing on?

It is to investigate the crustal deformation field in eastern Hokkaido and understand its mechanism. The Pacific side of this region has the potential of interplate large earthquakes along the Kuril Trench, and I think it is important to understand the current situation before the earthquake. In addition, there are many volcanoes such as the Kussharo caldera on the inland side, and complex crustal deformation fields occur because of volcanic activities and the inhomogeneous subsurface structure peculiar to volcanoes. I am working on research so that I can quantitatively understand and explain these phenomena.

Seafloor observation station before insertion. I am participating in a project to study the seafloor crustal movement around the Kuril Trench started in 2019. These stations were set up in three areas off Nemuro, and are repeatedly measuring the temporal changes of their location.
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What do you usually do when your research work gets stuck?

I give up that day, do something else, eat delicious food and get a good night’s sleep. Then, the next day, I try again. Sleep clears my head, and I can think about the things again. If that doesn’t work, I talk to the people around me. Talking to others can help me sort out my thoughts and find a breakthrough, and then I can start working again.

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Belongs