Work

Large submarine landslides in the Japan Trench: A new scenario for additional tsunami generation

Year: 2012

Type: article

Abstract: We describe in detail possible large submarine landslides, several tens of kilometers in length and width, on the trench landward slope of the Japan Trench on the basis of high‐resolution topographic surveys and detailed seafloor observations. These slides stopped at the toe of the trench slope. After initial movement of the toe along a basal decollement or thrust of the trench landward slope wedge during an earthquake, the basal frictional condition(s) might change drastically from static to dynamic, thus reducing the frictional strength. As a result, rapid submarine landsliding push downward on the toe, generating large horizontal displacements for tsunamis. This hypothesis should explain suitably the relation between large displacement of the thrust fault and tsunami generation by the 2011 Tohoku earthquake as well as tsunami generation by the 1896 Tohoku earthquake.

Source: Geophysical Research Letters

DOI: 10.1029/2011gl050661

Authors: Kiichiro Kawamura, Tomoyuki Sasaki, Toshiya Kanamatsu, Arito Sakaguchi, Yujiro Ogawa

Institutions: Japan Agency for Marine-Earth Science and Technology, Fukada Geological Institute, Atmosphere and Ocean Research Institute, The University of Tokyo, The University of Tokyo, University of Tsukuba

Language: English

Topic: earthquake and tectonic studies

Subfield: Geophysics

Field: Earth and Planetary Sciences

Domain: Physical Sciences

Open Access status: bronze

Funders: Ministry of Education, Culture, Sports, Science and Technology, Ministerio de Educación, Cultura y Deporte, Japan Society for the Promotion of Science, Japan Agency for Marine-Earth Science and Technology

Award: G3218377618