Title: | Seismicity controlled by resistivity structure : the 2016 Kumamoto earthquakes, Kyushu Island, Japan |
Authors: | Aizawa, Koki Browse this author |
Asaue, Hisafumi Browse this author |
Koike, Katsuaki Browse this author |
Takakura, Shinichi Browse this author |
Utsugi, Mitsuru Browse this author |
Inoue, Hiroyuki Browse this author |
Yoshimura, Ryokei Browse this author |
Yamazaki, Ken'ichi Browse this author |
Komatsu, Shintaro Browse this author |
Uyeshima, Makoto Browse this author |
Koyama, Takao Browse this author |
Kanda, Wataru Browse this author |
Shiotani, Taro Browse this author |
Matsushima, Nobuo Browse this author |
Hata, Maki Browse this author |
Yoshinaga, Tohru Browse this author |
Uchida, Kazunari Browse this author |
Tsukashima, Yuko Browse this author |
Shito, Azusa Browse this author |
Fujita, Shiori Browse this author |
Wakabayashi, Asuma Browse this author |
Tsukamoto, Kaori Browse this author |
Matsushima, Takeshi Browse this author |
Miyazaki, Masahiro Browse this author |
Kondo, Kentaro Browse this author |
Takashima, Kanade Browse this author |
Hashimoto, Takeshi Browse this author →KAKEN DB |
Tamura, Makoto Browse this author |
Matsumoto, Satoshi Browse this author |
Yamashita, Yusuke Browse this author |
Nakamoto, Manami Browse this author |
Shimizu, Hiroshi Browse this author |
Keywords: | Magnetotellurics |
Resistivity structure |
2016 Kumamoto earthquake |
Futagawa fault |
Hinagu fault |
Structural control |
Aso volcano |
Kuju volcano |
Tsurumi volcano |
Median Tectonic Line |
Issue Date: | 2017 |
Journal Title: | Earth, Planets and Space |
Volume: | 69 |
Issue: | 1 |
Start Page: | 4 |
Publisher DOI: | 10.1186/s40623-016-0590-2 |
Abstract: | The M JMA 7.3 Kumamoto earthquake that occurred at 1:25 JST on April 16, 2016, not only triggered aftershocks in the vicinity of the epicenter, but also triggered earthquakes that were 50–100 km away from the epicenter of the main shock. The active seismicity can be divided into three regions: (1) the vicinity of the main faults, (2) the northern region of Aso volcano (50 km northeast of the mainshock epicenter), and (3) the regions around three volcanoes, Yufu, Tsurumi, and Garan (100 km northeast of the mainshock epicenter). Notably, the zones between these regions are distinctively seismically inactive. The electric resistivity structure estimated from one-dimensional analysis of the 247 broadband (0.005–3000 s) magnetotelluric and telluric observation sites clearly shows that the earthquakes occurred in resistive regions adjacent to conductive zones or resistive-conductive transition zones. In contrast, seismicity is quite low in electrically conductive zones, which are interpreted as regions of connected fluids. We suggest that the series of the earthquakes was induced by a local accumulated stress and/or fluid supply from conductive zones. Because the relationship between the earthquakes and the resistivity structure is consistent with previous studies, seismic hazard assessment generally can be improved by taking into account the resistivity structure. Following on from the 2016 Kumamoto earthquake series, we suggest that there are two zones that have a relatively high potential of earthquake generation along the western extension of the MTL. |
Rights: | https://creativecommons.org/licenses/by/4.0/ |
Type: | article |
URI: | http://hdl.handle.net/2115/67561 |
Appears in Collections: | 理学院・理学研究院 (Graduate School of Science / Faculty of Science) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
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