タイトル(掲載誌)CEReS環境リモートセンシングシンポジウム資料集
一般注記type:text
[ABSTRACT] The dense continuous GPS Earth Observation Network of Japan (GEONET) has been established by the Geospatial Information Authority of Japan (GSI) since 1994. In this study, to understand the mega earthquake preparation process, we have investigated the long-term surface motion prior to the 2011 off the Pacific coast of Tohoku earthquake (Mw 9.0). Precise daily coordinates of GEONET stations have been utilized. Long-term linear trends of continuous GPS records have been analyzed and clear deformation velocity changes starting from about 1.4 year before the mega event have been detected. These changes of the surface deformation velocities suggest accelerations of stress accumulation. The spatial distributions of deformation velocities have shown westward directional changes in a large area along the Pacific coast. Based on these results, we have proposed an additional stage which is asperity upgrowth (or asperities synchronization) in the generation cycle of mega subduction earthquake. The proposed stage may be an essential difference between a mega event and a large one. Our results may help to understand the processes of mega subduction events.
一次資料へのリンクURLhttps://opac.ll.chiba-u.jp/da/curator/103924/BA64563608-18-P040.pdf
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース(IRDB)(機関リポジトリ)