地震地质 ›› 2009, Vol. 31 ›› Issue (4): 707-714.DOI: 10.3969/j.issn.0253-4967.2009.04.014

• 水库地震监测与研究 • 上一篇    下一篇

三峡水库地震活动特征研究

廖武林1,2, 张丽芬1,2, 姚运生2   

  1. 1. 中国地震局地球物理研究所, 北京, 100081;
    2. 中国地震局地震研究所, 武汉, 430071
  • 收稿日期:2009-07-13 修回日期:2009-11-08 出版日期:2009-12-24 发布日期:2010-04-17
  • 作者简介:廖武林,男,1976年生,中国地震局地球物理研究所在读博士研究生,副研究员,目前主要从事水库地震和地震波各向异性研究,电话:027-87166247,E-mail:lwldyx@163.com.
  • 基金资助:
    “十一五”国家科技支撑计划项目(2006BAC01B040202);国家自然科学基金(40674019);国家自然科学基金重点项目(40730317)共同资助

CHARACTERISTICS OF SEISMICITY IN THE THREE GORGES RESERVOIR AREA

LIAO Wu-lin1,2, ZHANG Li-fen1,2, YAO Yun-sheng2   

  1. 1. Institute of Geophysics, China Earthquake Administration, Beijing 100081, China;
    2. Institute of Seismology, China Earthquake Administration, Wuhan 430071, China
  • Received:2009-07-13 Revised:2009-11-08 Online:2009-12-24 Published:2010-04-17

摘要: 在已有速度模型的基础上,选取三峡水库区529个地震重新确定了速度模型和台站校正,并利用该结果对2 138次地震进行了定位。研究表明,在不同区域震源深度存在明显的差异,仙女山断裂附近的地震平均震源深度为5.6km,而巴东地区的地震平均震源深度为2.6km。以震源深度5km为界,浅于5km的地震的b值为1.16,而深于5km地震的b值为0.90,不同深度地震的频次变化与水位关系差异明显。

关键词: 地震定位, 三峡水库, 地震活动

Abstract: Accurate earthquake location is of primary importance in studying the seismicity of reservoir area. The well known program Velest was used to inverse the minimum 1-D velocity,hypocenter location and station correction simultaneously.We selected 529 earthquakes,which were recorded at least by 10 stations each and whose max azimuth gap was less than 180?,to re-determine the velocity model and station corrections with three different initial models used by different researchers before.Using the 1-D minimum velocity model and station correction,we relocated 2138 earthquakes in the Three Gorges area.The average focal depth changes remarkably in different areas,as 5.6km in the area near Xiannvshan Fault,2.9km in the Xietan area and 2.6km in the Badong area.Divided by the depth of 5km,the b values are different,as 1.07,1.16 and 0.90 for all,shallower and deeper events respectively. The frequency of shallower or deeper events per 15 days increases with impounding.But that of the shallower ones drops quickly and the deeper attenuates slowly when water lever keeps stable.

Key words: earthquake location, Three Gorges Reservoir, seismicity

中图分类号: