The Precursory Significance of Tectonic Stress Field Transformation before the Wenchuan Mw7.9 Earthquake and the Chi-Chi Mw7.6 Earthquake
详细信息
- 责任者：Diao Guiling (Earthquake Administration of Hebei Province ; Shijiazhuang 050021 ; China) ; Xu Xiwei
- 刊名：Chinese Journal of Geophysics
- 出版年：2011
- 卷期：54(1)
- 关键词：地震前兆 ; precursor ; 构造应力场 ; tectonic stress field ; 四川 ; Sichuan Province ; 台湾 ; Taiwan Province
- 页码：p.128-136
- 图表：7 illus., 1 table, 25 refs.
- 分类号：0500
- issnNo：ISSN0001-5733
- isbnNo：CN11-2074/P
摘要
The 2008 Wenchuan earthquake and the 1999 Chi-Chi earthquake are both intraplate thrust fault earthquakes occurred under the tectonic setting of thrust-nappe. Through comparative analysis on CMT solutions, focal mechanism solutions of small and moderate earthquakes, and tectonic stress field near the mainshock region, the authors found that the thrust type focal mechanism of the Chi-Chi mainshock coincides with the tectonic stress field derived from the CMT solutions of earthquakes occurred in central and western inland of Taiwan; but the small and moderate earthquakes randomly occurred near mainshock region resulted in strike slip type focal mechanisms, indicating the local stress field is not consistent with the tectonic stress field before the Chi-chi mainshock; the Chi-Chi mainshcok occurred after a few months when the local stress field is consistent with the tectonic stress field.