Japan Geoscience Union Meeting 2014

Presentation information

Poster

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

[S-SS30_29PO1] New perspective of great earthquakes along subduction zones

Tue. Apr 29, 2014 6:15 PM - 7:30 PM Poster (3F)

Convener:*Kanagawa Kyuichi(Graduate School of Science, Chiba University), Takashi Furumura(Center for Integrated Disaster Information Research (CIDIR) Interfaculty Initiative in Information Studies, The University of Tokyo), Shuichi Kodaira Shuichi(Institute for Research on Earth Evolution Japan Agency for Marine-Earth Science and Technology), Masanobu Shishikura(Active Fault and Earthquake Research Center, GSJ/AIST)

6:15 PM - 7:30 PM

[SSS30-P26] A structural traverse across the Shimanto belt in western Shikoku, Japan

*Kiyokazu OOHASHI1, Kyuichi KANAGAWA1 (1.Graduate School of Science, Chiba University)

Keywords:Shimanto accretionary complex, Out of sequence thrust, Melange, Vitrinite reflectance, Fault rocks

The Cretaceous and Tertiary Shimanto accretionary complex is largely characterized by imbricated thrust slices of trench-fill and ocean-floor sediments, and is thought as an ancient analog of the Nankai accretionary prism. Recent studies on a thermal structure and fault rock analysis for the Shimanto accretionary complex in the central and eastern Shikoku revealed that it has suffered earthquake faulting along the out-of-sequence thrusts associated with tectonic uplift. However, special distributions of thermal and tectonic structures are remaining unclear since those in the western part of Shikoku are poorly understood. In the presentation, we demonstrate the distributions and details of deformed rocks (e.g. melange and brittle faults), geological structure, and vitrinite reflectance across the Shimanto belt in western Shikoku.