Japan Geoscience Union Meeting 2016

Session information

Print

International Session (Oral)

Symbol S (Solid Earth Sciences) » S-SS Seismology

[S-SS02] Frontier studies on subduction zone megathrust earthquakes and tsunamis

Tue. May 24, 2016 3:30 PM - 5:00 PM IC (2F)

Convener:*Kyuichi Kanagawa(Graduate School of Science, Chiba University), Demian Saffer(Department of Geosciences, The Pennsylvania State University, USA), Michael Strasser(University of Innsbruck), James Kirkpatrick(McGill University), Shuichi Kodaira(R&D Center for Earthquake and Tsunami Japan Agency for Marine-Earth Science and Technology), Ryota Hino(Graduate School of Science, Tohoku University), Yasuhiro Yamada(Japan Agency for Marine-Earth Science and Technology (JAMSTEC), R&D Center for Ocean Drilling Science (ODS)), Kohtaro Ujiie(Graduate School of Life and Environmental Sciences, University of Tsukuba), Yoshihiro Ito(Disaster Prevention Research Institute, Kyoto University), Chair:Michael Strasser(University of Innsbruck), Yoshihiro Ito(Disaster Prevention Research Institute, Kyoto University)

Subduction zone megathrust earthquakes and their accompanying tsunamis, such as the Tohoku-oki earthquake on March 11 in 2011, have caused severe damage in the past. Scientists have worked for decades to understand these devastating events, mostly based on seismic, tsunami and geodetic observations. In addition to these remote monitoring studies, the challenge of drilling into and directly sampling megathrust faults at seismogenic depth, analysis of drill core and downhole logs, experiments on sampled fault materials, and borehole measurements at depth has recently been taken up or being planned by the Integrated Ocean Drilling or International Ocean Discovery Program at Nankai Trough (Nankai Trough Seismogenic Zone Experiment), Japan Trench (Japan Trench Fast Drilling Project and Tracking Tsunamigenic Slips in the Japan Trench), offshore Costa Rica (Costa Rica Seismogenesis Project), Sunda Trench (Sumatra Seismogenic Zone Expedition), and at the Hikurangi margin (Unlocking the Secrets of Slow Slip). In this session, we welcome presentations based on such frontier studies, in addition to those based on seismic, tsunami and geodetic observations, numerical modeling, and analyses of fault rocks exhumed from seismogenic depth.

4:00 PM - 4:15 PM

[SSS02-20] Spatial characteristics of postseismic deformation following the 2011 Tohoku-oki earthquake inferred from repeated GPS/Acoustic observations

*Fumiaki Tomita1, Motoyuki Kido2, Yusaku Ohta1, Ryota Hino1, Takeshi Iinuma3, Yukihito Osada1,4 (1.Graduate School of Science and Faculty of Science, Tohoku University, 2.International Research Institute of Disaster Science, Tohoku University, 3.Japan Agency for Marine-Earth Science and Technology, 4.GNSS Technologies Inc.)

4:15 PM - 4:30 PM

[SSS02-21] Spatiotemporal changes in the b-value along the plate interface before and after the 2011 Tohoku earthquake constrained by ocean bottom seismic network: Post-Tohoku

*Yukihiro Nakatani1, Kimihiro Mochizuki1, Masanao Shinohara1, Tomoaki Yamada1, Hajime Shiobara1, Ryota Hino2, Ryosuke Azuma2, Yoshihiro Ito3, Yoshio Murai4, Toshinori Sato5, Kenji Uehira6, Takashi Shimbo6, Hiroshi Yakiwara7, Shuichi Kodaira8, Yuya Machida8, Kenji Hirata9, Hiroaki Tsushima9 (1.Earthquake Research Institute, University of Tokyo, 2.Graduate School of Science, Tohoku University, 3.Disaster Prevention Research Institute, Kyoto University, 4.Institute of Seismology and Volcanology, Faculty of Science, Hokkaido University, 5.Graduate School of Science, Chiba University, 6.National Research Institute for Earth Science and Disaster Prevention, 7.Nansei-toko Observatory for Earthquakes and Volcanoes, Faculty of Science, Kagoshima University, 8.Japan Agency for Marine-Earth Science and Technology, 9.Meteorological Research Institute, Japan Meteorological Agency)

4:30 PM - 4:45 PM

[SSS02-22] Seismic monitoring in the northern source region of the 2011 Tohoku-oki earthquake by using long-term OBSs

*Masanao Shinohara1, Tomoaki Yamada1, Kimihiro Mochizuki1, Takeshi Akuhara1, Yukihiro Nakatani1, Hajime Shiobara1, Yoshio Murai2, Shinya Hiratsuka2, Ryota Hino3, Yusaku Ohta3, Ryosuke Azuma3, Toshinori Sato4, Yoshihiro Ito5, Yusuke Yamashita5, Kazuo Nakahigashi6, Takuya Teraoka6, Hiroshi Yakiwara7 (1.Earthquake Research Institute, University of Tokyo, 2.Institute of Seismology and Volcanology, Hokkaido University, 3.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Tohoku University, 4.Faculty of Science, Chiba University, 5.Disaster Prevention Research Institute, Kyoto University, 6.Faculty of Science, Kobe University, 7.Nansei-Toko Observatory for Earthquakes and Volcanoes, Kagoshima University)

4:45 PM - 5:00 PM

[SSS02-23] Amplitude changes of the seismic reflected phases from the plate interface before and after the 2011 Tohoku earthquake around its northern limit region as revealed by active seismic surveys

Ken Ishihara1, *Kimihiro Mochizuki1, Tomoaki Yamada1, Masanao Shinohara2, Yusuke Yamashita3, Ryosuke Azuma4, Ryota Hino4, Toshinori Sato5, Yoshio Murai6, Hiroshi Yakiwara7 (1.Earthquake Prediction Research Center, Earthquake Research Institute, University of Tokyo, 2.Center for Geophysical Observatoin and Instrumentation, Earthquake Research Institute, University of Tokyo, 3.Miyazaki Observatory, Research Center for Earthquake Prediction, Disaster Prevention Research Institute, Kyoto University, 4.Resarch Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 5.Faculty of Science, Chiba University, 6.Institute of Seismology and Volcanology, Faculty of Science, Hokkaido University, 7.Nansei-Touko Observatory for Earthquakes and Volcanoes, Faculty of Science, Kagoshima University)