open access

https://doi.org/10.14943/gbhu.73.129

https://hdl.handle.net/2115/44464

Characterized Source Model of Intraslab Earthquakes for Strong Ground Motion Prediction

日本語

2010-03-19

北海道大学大学院理学研究院自然史科学部門（地球物理学）

Geophysical bulletin of Hokkaido University

73

129-135

We study characterized source model for the strong motion prediction of intraslab earthquakes in the same manner as crustal earthquakes （Somerville et al., 1999） and interplate earthquakes （Murotani et al., 2009）. We characterized the heterogeneous slip distributions of 11 events with MW 6.6-8.3 and determined rupture area（S）, total asperity area（Sa）, and average slip（D）with following the procedure proposed by Somerville et al.（1999）. Assuming power of 2/3 dependency of S and Sa on seismic moment and that of 1/3 for D, we got the empirical relationships as follows, S（km2 ）＝ 6.57×10-11×M0 2/3（Nm） Sa（km2 ）＝ 1.04×10-11×M0 2/3（Nm） D（cm）＝ 2.25×10-5×M0 2/3（Nm） The stress parameters on and off asperities are estimated as 28.9 MPa and 4.6 MPa, respectively, from the asperity model by Boatwright（1988）. We also summarized size and position of strong motion generation area（SMGA, Miyake et al., 2003）for intraslab earthquakes by broad-band ground motion simulations. We found SMGA corresponds to the asperity and the size of SMGA is equivalent to or a little bit smaller than the asperity size. Based on these characteristics, we propose the characterized source model of intraslab earthquakes for strong ground motion prediction. We confirmed the procedure by simulating strong ground motions for the 2001 Geiyo earthquake（MW 6.8, hypocentral depth＝46 km）. Using these empirical relationships, we constructed the characterized source models for the 2001 Geiyo earthquake and simulated ground motions at strong motion observation sites using the empirical Green's function method.

紀要論文

Version of Record

0439-3503

AN0008976X