Relocation of the 1999 Chi-Chi Earthquake in Taiwan
Journal
Terrestrial, Atmospheric and Oceanic Sciences
Journal Volume
11
Journal Issue
3
Pages
581-590
Date Issued
2000
Author(s)
Abstract
The 1999 Chi-Chi earthquake in Taiwan represented the island's larg est inland seismic event of the last century. This earthquake severely struck the western-middle part of the island. Abundant high-resolution digital seis mic data were recorded by two seismic networks operated by the Central Weather Bureau (CWB). In this paper, we combined data from two CWB seismic networks to analyze the characteristics of the Chi-Chi earthquake sequence. The mainshock was relocated to 23.853N, 120.816E at the depth of 8 km. The focal mechanism was of a thrust type with strike 5, dip 34 and rake 65 based on the new location and the first motion polarities. The distribution of the aftershocks revealed a special distribution pattern which marked out an aseismic dipping plane with the aftershocks mostly occur ring on its upper side. It is highly suggested that there is a close relationship between this aseismic dipping plane and the Chelungpu fault .
Type
journal article