欢迎访问《地震》,

地震 ›› 2019, Vol. 39 ›› Issue (2): 110-121.

• • 上一篇    下一篇

中国大陆及其周边地区应力场特征

田建慧, 罗艳   

  1. 中国地震局地震预测研究所地震预测重点实验室, 北京 100036
  • 收稿日期:2018-10-30 出版日期:2019-04-30 发布日期:2019-08-09
  • 通讯作者: 罗艳, 副研究员。 E-mail: luoyan.wind@gmail.com
  • 作者简介:田建慧(1994-), 女, 甘肃张掖人, 在读硕士研究生, 主要从事震源机制解、 构造应力场解释与研究
  • 基金资助:
    中国地震局地震预测研究所基本科研业务费专项(2015IES010302)和大地测量与地球动力学国家重点实验室开放基金(SKLGED2018-4-3-E)共同资助

Characteristics of Stress Field in Mainland China and Surrounding Areas

TIAN Jian-hui, LUO Yan   

  1. Institute of Earthquake Forecasting, CEA, Beijing 100036, China
  • Received:2018-10-30 Online:2019-04-30 Published:2019-08-09

摘要: 本文收集了1976—2018年发生在中国大陆及其周边地区(15°~55°N, 65°~125°E)的4303个地震震源机制解, 分析了该区震源机制解和P、 T轴空间分布特征, 并使用这些震源机制解, 反演得到了中国大陆及周边地区二维构造应力场分布。 应力场反演结果表明, 云南大部、 青藏高原大部以及华北华南大部以走滑型应力性质为主, 印度洋板块与欧亚板块的强烈碰撞控制着中国西部地区, 大量的逆断型地震集中分布在青藏高原周缘和西域活动地块的天山地区。 青藏高原内部也存在正断型地震, 且应力场方向在26°N发生了很大的变化。 位于青藏高原东构造线以南的滇缅活动块体, 最大主压应力σ1方向在大致100°E发生突变, 由以西的NNE方向偏转到NNW方向。 中国东部的东北块体到华北块体再到华南块体, 最大主压应力方向有一个从NE向逐渐转变成EW向再变化到NW向的旋转趋势。 应力场总体结果表明, 中国东部应力场主要受到太平洋板块和菲律宾板块对欧亚大陆俯冲的作用, 中国西部主要受印度板块向北碰撞欧亚大陆的影响, 块体内部相互作用、 块体与断裂带相互作用也对应力场变化产生影响。

关键词: 构造应力场, 震源机制解, 中国大陆

Abstract: In this paper, focal mechanism solutions of 4303 earthquakes occurred in and around the mainland of China (15°~55°N, 65°~125°E) from 1976 to 2018 are collected, and the focal mechanism solutions and the spatial distribution characteristics of the P, T axis are analyzed. Using these focal mechanism solutions, we obtained a 2-D tectonic stress field distribution. The results of stress field inversion show that the strike-slip stress is dominant in most of Yunnan, most of the Tibet Plateau and most of North and South China. The strong collision between the Indian plate and the Eurasian plate controls the western part of China. A large number of fault-type earthquakes are concentrated in the Tibet Plateau and the Tianshan area of active block in the western region. There are also normal fault type earthquakes in the Tibet Plateau interior, and the direction of the stress field changes greatly at 26°N. In the Yunnan-Myanmar active block located south of the eastern tectonic line of the Tibet Plateau, the direction of the maximum principal compressive stress changes from the direction of NNE to the direction of NNW. From the northeast block to the North China block and the South China block, the maximum principal compressive stress direction has a rotational tendency from NE to EW and NW.

Key words: Stress field, Focal mechanisms, Mainland China

中图分类号: