| 2009年姚安MS6.0地震序列发震断层及应力场特征 |
| |
| 引用本文： | 李君,王勤彩.2009年姚安MS6.0地震序列发震断层及应力场特征[J].地震学报,2016,38(2):199-207. |
| |
| 作者姓名： | 李君 王勤彩 |
| |
| 作者单位： | 1.中国北京 100036 中国地震局地震预测研究所 |
| |
| 基金项目： | 中国地震局地震预测研究所重点项目2014IES010204国家自然基金青年科学基金41404047 |
| |
| 摘 要： | 本文使用2009年7月9日—12月23日2009年姚安MS6.0地震序列中ML≥1.0地震的震相数据， 采用双差定位法对该序列进行重定位， 共得到643次地震的精定位结果； 利用P波初动和振幅比法获取了20次ML≥3.0地震的震源机制解； 在此基础上采用滑动拟合法得到姚安MS6.0地震序列的震源区应力场． 研究结果表明: ① 2009年姚安MS6.0地震序列的发震断层为NW走向、 NE倾向的高角度右旋走滑断层； ② 该序列的余震条带延伸方向与2000年姚安MS6.5地震序列一致， 两次主震震源机制解一致且两个地震序列均发生在马尾箐断裂上， 2009年姚安MS6.0地震序列是马尾箐断裂向NW方向的延伸； ③ 姚安MS6.0地震震源区的最大主应力方向为NNW--SSE向， 接近水平, 与区域应力场方向一致； ④ 2009年姚安MS6.0地震序列是在区域应力增强的背景下， 位于高低速过渡带高速一侧的震源区应力高度积累， 使得马尾箐断裂向NW方向破裂扩展的结果．
|
| 关 键 词： | 姚安MS6.0地震序列 双差定位法 P波初动法 振幅比法 应力场 |
| 收稿时间： | 2015-09-16 |
Seismogenic faults and stress field characteristics of MS6.0 Yao’an earthquake sequence in 2009 |
| |
| Affiliation: | 1.Institute of Earthquake Science, China Earthquake Administration, Beijing 100036, China2.Key Laboratory of Earthquake Prediction, China Earthquake Administration, Beijing 100036, China |
| |
| Abstract: | This paper adopted double difference earthquake location algorithm to relocate the earthquakes with ML≥1.0 of the MS6.0 Yao'an earthquake sequence in 2009 from July 9 to December 23, 2009, and obtained precise locations of 643 earthquakes, and then the focal mechanisms of 20 earthquakes with ML≥3.0 were determined by using the first motion of P-wave and amplitude ratio method. The stress field of MS6.0 Yao'an earthquake sequence are obtained by using moving fitting method. The results show that: ① The seismogenic fault of MS6.0 Yao'an earthquake sequence in 2009 is of right-lateral strike-slip type with NW trending, NE dipping, and high-angle. ② The extend-ing direction of MS6.0 Yao'an earthquake sequence in 2009 is consistent with that of the MS6.5 Yao'an earthquake sequence in 2000, so does the focal mechanism solution of mainshock. Both of the two sequences occurred on Maweiqing fault, and the sequence in 2009 occurred on the NE-trending extending of Maweiqing fault. ③ The stress field of MS6.0 Yao'an earthquake sequence in 2009 trends in NNW-SSE direction, which is coincident with the regional stress field. ④ With the strengthening of regional stress field, the stress accumulation in the source region located at the higher velocity side of transitional zone alternating between high and low velocity zones makes the Maweiqing fault extend NE-wards, resulting in the occurrence of Yao'an earthquake sequence in 2009. |
| |
| Keywords: | |
|
| 点击此处可从《地震学报》浏览原始摘要信息 |
|
点击此处可从《地震学报》下载全文 |
|
