Review:

# The Advancement of Research on Inland Earthquake Generation 2014–2018

## Satoshi Matsumoto^{*1,†}, Tomomi Okada^{*2}, Toshiko Terakawa^{*3}, Makoto Uyeshima^{*4}, and Yoshihisa Iio^{*5}

^{*1}Institute of Seismology and Volcanology, Faculty of Science, Kyushu University

2-5643-29 Shinyama, Shimabara, Nagasaki 855-0843, Japan

^{†}Corresponding author

^{*2}Graduate School of Science, Tohoku University, Miyagi, Japan

^{*3}Graduate School of Environmental Studies, Nagoya University, Aichi, Japan

^{*4}Earthquake Research Institute, The University of Tokyo, Tokyo, Japan

^{*5}Disaster Prevention Research Institute, Kyoto University, Kyoto, Japan

The 2011 Tohoku-Oki Earthquake (M9.0) significantly affected inland areas of Japan. The crust and mantle response to the magathrust earthquake induced changes in the mechanical conditions of the seismogenic zone. Here we present important progress in the research into the seismogenesis of inland earthquakes. Stress, strain, strength, and structures are key parameters affecting the occurrence of earthquakes. In particular, both the spatial and temporal changes in these parameters around the focal areas of the large inland earthquakes have been detected and modeled. These results have provided spatial potential evaluation in terms of future inland earthquake occurrence. However, we clearly recognize that, in order to understand and predict the inland earthquake generation process, it will inevitably be necessary to unify the research on various spatial and temporal scales, from problems related to long-term stress loading from plate-relative motion to instant fault response.

*J. Disaster Res.*, Vol.15, No.2, pp. 96-105, 2020.

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