Finite-element simulations of long-period ground motions: Japanese subduction-zone earthquakes and the 1906 San Francisco earthquake

Large earthquakes at shallow depths commonly excite long-period ground motions in distant sedimentary basins, thereby inflicting damage upon large-scale structures. For example, the 2003 Tokachi-oki earthquake, Japan, damaged oil tanks in the Yufutsu Basin, located 250 km from the epicenter. Similar long-range effects were also observed during the 2004 earthquake off Kii Peninsula, Japan. In this study, we present the results of simulations of these earthquakes undertaken using the finite element method (FEM) with a voxel mesh. In addition, to examine whether the 1906 San Francisco earthquake excited long-period ground motions in the Los Angeles-area basins, we performed long-period ground motion simulations of most of the California region. The FEM simulations confirmed the importance of path effects for the development of long-period ground motions.

[1]  Robert W. Graves,et al.  The SCEC Southern California Reference Three-Dimensional Seismic Velocity Model Version 2 , 2000 .

[2]  Kim B. Olsen,et al.  Estimation of Q for Long-Period (>2 sec) Waves in the Los Angeles Basin , 2003 .

[3]  Wayne Thatcher,et al.  Resolution of fault slip along the 470‐km‐long rupture of the great 1906 San Francisco earthquake and its implications , 1997 .

[4]  K. Hatayama,et al.  Control Factors of Spatial Variation of Long-Period Strong Ground Motions in the Yufutsu Sedimentary Basin, Hokkaido, during the Mw 8.0 2003 Tokachi-oki, Japan, Earthquake , 2007 .

[5]  Thomas H. Heaton,et al.  Relationships between Peak Ground Acceleration, Peak Ground Velocity, and Modified Mercalli Intensity in California , 1999 .

[6]  T. Brocher.  Empirical relations between elastic wavespeeds and density in the Earth's crust , 2005 .

[7]  Arben Pitarka,et al.  3D Elastic Finite-Difference Modeling of Seismic Motion Using Staggered Grids with Nonuniform Spacing , 1999 .

[8]  T. Brocher.  A Regional View of Urban Sedimentary Basins in Northern California Based on Oil Industry Compressional-Wave Velocity and Density Logs , 2005 .

[9]  K. Kohketsu.  The extended reflectivity method for synthetic near-field seismograms , 1985 .

[10]  Gregory C. Beroza,et al.  A Unified Source Model for the 1906 San Francisco Earthquake , 2008 .

[11]  J. F. Hall,et al.  Factors contributing to the catastrophe in Mexico City during the earthquake of September 19, 1985 , 1986 .

[12]  Robert W. Graves,et al.  Simulating seismic wave propagation in 3D elastic media using staggered-grid finite differences , 1996, Bulletin of the Seismological Society of America.

[13]  K. Olsen,et al.  Wave‐guide effects in subduction zones: Evidence from three‐dimensional modeling , 2000 .

[14]  Hiroyuki Fujiwara,et al.  Finite-element Simulation of Seismic Ground Motion with a Voxel Mesh , 2004 .

[15]  S. Miyazaki,et al.  Joint inversion of strong motion and geodetic data for the source process of the 2003 Tokachi-oki, Hokkaido, earthquake , 2004 .

[16]  T. Furumura,et al.  Simulation of strong ground motions caused by the 2004 off the Kii peninsula earthquakes , 2005 .

[17]  H. O. Wood,et al.  Modified Mercalli intensity scale of 1931 , 1931 .

[18]  Thomas H. Heaton,et al.  Source study of the 1906 San Francisco earthquake , 1993, Bulletin of the Seismological Society of America.

[19]  K. Koketsu,et al.  Long-period ground motions from a large offshore earthquake: The case of the 2004 off the Kii peninsula earthquake, Japan , 2005 .

[20]  Thomas M. Brocher,et al.  Compressional and Shear Wave Velocity Versus Depth in the San Francisco Bay Area, California: Rules for USGS Bay Area Velocity Model 05.0.0 , 2005 .

[21]  J. Boatwright,et al.  Modified mercalli intensity maps for the 1906 San Francisco earthquake plotted in ShakeMap format , 2005 .

[22]  T. Furumura,et al.  Damaging Long-period Ground Motions from the 2003 Mw 8.3 Tokachi-oki, Japan Earthquake , 2005 .