SEISMOLOGY AND EGOLOGY ›› 2015, Vol. 37 ›› Issue (1): 126-138.DOI: 10.3969/j.issn.0253-4967.2015.10

• CONTENTS • Previous Articles     Next Articles

EFFECT OF FAULT STEPS ON PROPAGATION AND TERMINATION BEHAVIOR OF STRIKE-SLIP EARTHQUAKE SURFACE RUPTURES

LI Zheng-fang1, XIAO Hai-bo2, ZHOU Ben-gang1   

  1. 1 Key Laboratory of Active Tectonics and Volcano, Institute of Geology, China Earthquake Administration, Beijing 100029, China;
    2 PowerChina Beijing Engineering Corporation Limited, Beijing 100024, China
  • Received:2013-09-28 Revised:2014-09-12 Online:2015-03-20 Published:2015-05-15

阶区对走滑型地震地表破裂带传播与终止行为的影响

李正芳1, 肖海波2, 周本刚1   

  1. 1 中国地震局地质研究所, 活动构造与火山重点实验室, 北京 100029;
    2 中国电建集团北京勘测设计研究院有限公司, 北京 100024
  • 作者简介:李正芳,女,1981年生,2013年在中国地震局地质研究所获构造地质学专业博士学位,助理研究员,主要研究方向为工程地震与地震危险性分析,电话:010-62009143,E-mail:lizhengfang2012@163.com。
  • 基金资助:

    中国地震局地震行业科研专项(2015419024)和中国地震局地质研究所基本科研业务专项(IGCEA1310)共同资助

Abstract:

Based on the data of 28 strike-slip fault steps and the surface rupture traces at home and abroad, the paper analyzes the relations between the step type, size and earthquake rupture by using the mathematical statistical method, and obtains the barriers yardsticks that stop rupture propagation of earthquakes with different magnitude intervals by using the method of statistical analysis. The results show that the limiting dimensions of strike-slip fault step are different for different magnitude intervals. The limiting dimension of step width is about 3km for magnitude between 6.5 to 6.9, 4km for magnitude between 7.0 to 7.5, 6km for magnitude between 7.5 to 8.0, and about 8km for magnitude between 8.0 to 8.5. The result implies that releasing steps should be easier to rupture through than restraining steps. The limiting dimension of step width determined in this paper is basis for rupture segmentation and is of practical importance to seismic hazard analysis.

Key words: strike-slip earthquake, surface rupture zone, fault step, the limiting dimension

摘要:

系统收集了国内外28个走滑地震破裂带上阶区与地震破裂行迹的资料, 利用数理统计的方法分析了阶区的类型、尺度与地震破裂的关系。结果表明, 不同震级档的走滑地震阶区限制破裂传播的止裂尺度是不同的, 震级MS 为6.5~6.9, 阶区的最小止裂宽度约为3km;震级MS 为7.0~7.5, 阶区的最小止裂宽度约为4km;震级MS 为7.5~8.0, 阶区的最小止裂宽度约为6km;震级MS 为8.0~8.5, 阶区的最小止裂宽度约为8km;且拉分阶区比挤压阶区更容易被破裂所贯通。上述给出的阶区的最小止裂宽度可作为判定地震破裂止裂尺度的重要标志, 是进行破裂分段的前提和基础, 对地震危险性分析具有重大的实用价值。

关键词: 走滑地震, 地表破裂带, 阶区, 止裂尺度

CLC Number: