Strong Ground-Motion Simulation of the 12 May 2008 MW 7.9 Wenchuan Earthquake, Using Various Slip Models.

Autor: Bjerrum, Louise W., Sørensen, Mathilde B., Atakan, Kuvvet
Předmět:
Zdroj: Bulletin of the Seismological Society of America; Nov2010, Vol. 100 Issue 5B, p2396-2424, 29p, 1 Black and White Photograph, 1 Diagram, 5 Charts, 19 Graphs, 1 Map
Abstrakt: On 12 May 2008, a devastating earthquake of MW 7.9 occurred in the Sichuan Province of China. The earthquake had disastrous consequences and cost more than 69,000 lives. The rupture occurred along a 300-km-long fault dipping northwest along the Longmen Shan fold-thrust belt, which separates the Longmen Shan of the Tibetan Plateau in the northwest from the Sichuan Basin in the southeast and is associated with a significant change in the crustal thickness. We simulate the ground shaking due to the Wenchuan earthquake by applying a hybrid broadband frequency strong ground-motion simulation technique that combines deterministic simulation of low frequencies (0.1-1.0 Hz) with semistochastic modeling of high frequencies (1.0-10 Hz). We use three available finite fault-slip models obtained from waveform inversion as input models for the earthquake scenarios. The resulting simulations reveal large variations in ground shaking due to the rupture complexity in terms of a variety of factors, including the location of asperities and the width of the fault plane. The applied methodology successfully reproduces the strong ground-motion distribution and frequency content of the seismic waves. The simulated ground motions, when calibrated with the recorded data, can also be used to verify the finite fault-slip models based on different teleseismic data and inversion schemes. Comparison with the damage distribution from reconnaissance field observations confirms the fault rupture complexity. The applied simulation methodology provides a promising platform for predictive studies. [ABSTRACT FROM AUTHOR]
Databáze: Supplemental Index