Out-of-sequence thrust faults developed in the coseismic slip zone of the 1946 Nankai earthquake (Mw=8.2) off Shikoku, southwest Japan

被引：42

作者：

Park, JO

Tsuru, T

Kodaira, S

Nakanishi, A

Miura, S

Kaneda, Y

Kono, Y

Takahashi, N

机构：

[1] Japan Marine Sci & Technol Ctr, Frontier Res Program Subduct Dynam, Yokosuka, Kanagawa 2370061, Japan

[2] Japan Marine Sci & Technol Ctr, Deep Sea Res Dept, Yokosuka, Kanagawa 2370061, Japan

来源：

GEOPHYSICAL RESEARCH LETTERS | 2000年 / 27卷 / 07期

关键词：

D O I：

10.1029/1999GL008443

中图分类号：

P [天文学、地球科学];

学科分类号：

07 ;

摘要：

A multi-channel seismic (MCS) reflection survey was conducted to study the subsurface structure of the coseismic slip zone of the 1946 Nankai earthquake (Mw=8.2) off Shikoku Island in 1997. We could identify a splay fault system consisting of several sigmoid out-of-sequence thrust (OST) faults dipping landward with slope 10 similar to 25 degrees on the poststack depth migrated MCS profiles. Most of the OSTs are apparently developed from the subducting oceanic basement to the seafloor in the forearc region, cutting both underthrust sediments and the overriding accretionary prism. In addition, most of the OSTs are within the coseismic zone of the 1946 Nankai earthquake and the interseismic locked zone. The OSTs are considered to be related to large interplate earthquakes including the 1946 Nankai earthquake. These OSTs may be responsible for tsunami generation following deformation of forearc accretionary wedge.

引用

页码：1033 / 1036

页数：4