The characteristics of near-fault ground motion are investigated considering heterogeneous slip distribution on the fault plane. Areas on the fault plane with large slip in compare with the average slip on the fault are known as asperity. The characteristics of strong ground motions in near-fault area are strongly affected by faulting parameters such as asperity location, maximum slip of asperi...

We treat a fault as an array of asperities with a prescribed statistical distribution of strengths. When an asperity fails, the stress on the failed asperity is transferred to one or more adjacent asperities. For a linear array the stress is transferred to a single adjacent asperity and for a two-dimensional array to three adjacent asperities. Using a renormalization group (RG) method, we inves...

The 1999 Chi-Chi earthquake (MW 7.6) (20 September 1999, 17:47:15.9 UTC) (located at 23.853 N, 120.816 E, and depth of 7.5 km) inflicted severe regional scale damage to Taiwan. The strong-motion wavefield was captured by a dense network of stations (with average station spacing of 5 km), which represents the most complete strong-motion dataset to date to use to study the kinematic source proces...

[1] The ground motion data of the 1999 Chi-Chi, Taiwan, earthquake exhibit a striking difference in frequency content between the north and south portions of the rupture zone. In the north, the ground motion is dominated by large lowfrequency displacements with relatively small high-frequency accelerations. The pattern is opposite in the south,with smaller displacements and larger accelerations...

Ruff, L.J., 1992. Asperity distributions and large earthquake occurrence in subduction zones. In: T. Mikumo, K. Aki, M. Ohnaka, L.J. Ruff and P.K.P. Spudich (Editors), Earthquake Source Physics and Earthquake Precursors. Tectonophysics. 211: 61-83. Plate tectonics and the seismic gap hypothesis provide the framework for long-term earthquake forecasting of plate boundary earthquakes. Unfortunate...

A strength profile across the NE Japan interplate megathrust was constructed in the source region of the 2011 Tohoku-oki earthquake (Mw9.0) using friction, fracturing, and ductile flow data of the oceanic crustal materials obtained from laboratory experiments. The depth-dependent changes in pressure, temperature, and pore fluid pressure were incorporated into a model. The large tsunamigenic sli...

Numerical models of earthquake rupture are used to investigate characteristic length scales and size distributions of repeated earthquakes on vertical, planar fault segments. The models are based on exact solutions of static three-dimensional (3-D) elasticity. Dynamical rupture is approximated by allowing the static stress field to expand from slip motions at a single velocity. To show how the ...

The peak of smooth Fourier amplitude spectra, (FS(T))max, of strong motion acceleration recorded in California is modeled via dimensional analysis. In this model, the spectrum amplitudes are proportional to (1) – the root-mean-square (r.m.s.) amplitude of the peak stresses on the fault surface in the areas of high stress concentration (asperities), and (2) (log10 N)1/2, where N is the number of...

The cause of asperities (i.e., high-slip regions) remains the subject of much debate in seismology. Several tomography studies have reported previously that high-velocity bodies coincide with asperities. However, it remains unclear whether the heterogeneity of the crust generates these asperities. This can be addressed by conducting stress analysis. The 2004 Chuetsu, Japan earthquake is one of ...