Active deformation of Sagami Bay triggered by approach of the Izu island arc
Active deformation of Sagami Bay triggered by approach of the Izu island arc
复制标题
伊豆岛弧逼近引发相模湾主动变形
DOI：
10.1007/s00367-020-00668-2
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发表时间：
2020
影响因子：
2.1
通讯作者：
Kinoshita Masataka
中科院分区：
文献类型：
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作者：
Misawa Ayanori;Ashi Juichiro;Tara Kenji;Yamashita Mikiya;Kinoshita Masataka
日本中部的相模湾被认为是1703年和1923年关东地震的发震和海啸带，在东京大都市区造成了毁灭性的破坏。然而，在最后一次灾难性事件之后，俯冲带锋面楔内的海啸成因构造仍未得到解决。利用地震反射、深拖曳高分辨率海底剖面和带状测深资料，揭示了相模湾相模构造线最浅层构造的详细构造特征。根据我们的数据，分布在三浦丘陵西南边缘的相模构造线中段，被认为极有可能是一个反复活动的活动断层。相模湾南部的槽状充填沉积物目前被认为是受菲律宾海板块伊豆-小笠原弧地壳尖端向西北俯冲的压应力的积极变形。
Sagami Bay in central Japan is known as the seismogenic and tsunamigenic zone of the 1703 and 1923 Kanto earthquakes that caused devastating damage in the Tokyo metropolitan area. However, the tsunamigenic structure within the frontal wedges of the subduction zone remains unresolved after the last disastrous events. In the present study, the detailed structural features of the shallowest structure of the Sagami Tectonic Line in Sagami Bay were revealed by seismic reflection, a deep-towed high-resolution sub-bottom profiler, and swath bathymetry data. Based on our data, the middle segments of the Sagami Tectonic Line, which is distributed along the southwestern rim of the Miura Knoll, are considered highly likely to be an active fault that has been a repeatedly active feature. The trough-fill sediments of the south Sagami Bay are currently thought to be actively deformed by the compressive stress accompanying northwestward subduction of the tip of Izu-Ogasawara (Bonin) Arc crust on the Philippine Sea plate.