SEISMOLOGY AND GEOLOGY ›› 2006, Vol. 28 ›› Issue (3): 391-404.

• Brief Report • Previous Articles     Next Articles

LATE-QUATERNARY HORIZONTAL DISPLACEMENT AND ITS ASSOCIATED MICROGEOMORPHOLOGY OF THE WESTERN QINLING FAULT ZONE AT HUANGXIANGGOU

LI Chuan-you1, ZHANG Pei-zhen1, YUAN Dao-yang1, WANG Zhi-cai1, ZHANG Jian-xi2   

  1. 1. Institute of Geology, China Earthquake Administration, Beijing 100029, China;
    2. Beijing Earthquake Administration, Beijing 100080, China
  • Received:2006-04-05 Revised:2006-06-28 Online:2006-09-14 Published:2009-08-27

西秦岭北缘断裂带黄香沟段晚第四纪水平位移特征及其微地貌响应

李传友1, 张培震1, 袁道阳1, 王志才1, 张剑玺2   

  1. 1. 中国地震局地质研究所, 北京, 100029;
    2. 北京市地震局, 北京, 100080
  • 作者简介:李传友,男,1971年出生,2005年毕业于中国地震局地质研究所地震地质学专业,获得博士学位,主要从事活动构造、新构造与构造地貌等方面的研究,电话:010-62009033,E-mail:lchyou@hotmail.com.
  • 基金资助:
    国家自然科学基金(40234040);地震科学联合基金(103040)共同资助

Abstract: The western Qinling Fault zone is one of the main left-lateral strike-slip active faults in northeastern Tibet. At site of Huangxianggou, the behavior of the fault zone shows typical strike-slip movement. Detailed analysis on the amounts of the offset of the late Quaternary landforms and geologic bodies along the fault shows that at Huangxianggou the maximum horizontal displacement since the late of late-Pleistocene is about 40~60m, and the minimum is 6~8m which is possibly the amount of one principal slip associated with one large earthquake event. And it is also inferred that the amounts of the displacement along the fault can be grouped, and between the groups there is a stable increment of 6~8m. The grouping and the increment of amounts of the offsets suggest that this fault segment displays an activity associated with characteristic earthquakes, and the 7 groups of the displacement values represent 7 characteristic events on the fault. Analysis on the microgeomorphology related to the faulting, such as periodic sag-ponding and deformed pluvial fans, also suggests the corresponding events. Thus it can be inferred, the activity of the fault zone has been dominated by several strong movements since late Late-Pleistocene.

Key words: western Qinling Fault zone, horizontal displacement, microgeomorphology, characteristic events

摘要: 西秦岭北缘断裂带是青藏高原东北部一条左旋走滑为主的活动断裂带,其在黄香沟一段活动性较强,活动现象典型。对沿断裂带分布的地貌、地质体等晚第四纪位移量的研究表明,在黄香沟一带,断裂晚更新世晚期以来的水平位移量最大为40~60m;最小为6~8m,可能是一次滑动事件的特征位错量。断裂带上的位移具有分组特征,各组位移值之间具有6~8m的稳定增量。位移值的分组性和增量特征反映了该段断裂具有特征地震的活动特征,而7组位错值则反映了断裂7次特征活动事件。关于黄香沟一带与断裂相关的微地貌分析,也获得了大致相对应的事件次数。并由此初步推测,晚更新世晚期以来,该断裂带有过多次强烈活动,活动期次明显。

关键词: 西秦岭北缘断裂带, 水平位移, 微地貌, 特征事件

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