川西及其邻近地区活动构造基本特征与强震复发模型  

FEATURES OF ACTIVE TECTONICS AND RECURRENCE BEHAVIORS OF STRONG EARTHQUAKES IN THE WESTERN SICHUAN PROVINCE AND ITS ADJACENT REGIONS

作　　者：徐锡伟[1] 张培震[1] 闻学泽[2] 秦尊丽[3] 陈桂华[1] 朱艾斓[1] 

机构地区：[1]中国地震局地质研究所,北京100029 [2]四川省地震局,成都610041 [3]北京国电水利电力工程有限公司,北京100024

出　　处：《地震地质》2005年第3期446-461,共16页Seismology and Geology

基　　金：国家重点基础研究发展规划项目(2004CB418401);国家科技基础平台重点项目(2003DIA6N005)共同资助。

摘　　要：川西及其邻近地区位于青藏高原东缘川滇、巴颜喀拉和华南三大活动块体的交接部位,发育着多组具有发震能力的活动断裂。由于横向次级活动断裂的存在,川滇块体可进一步划分为滇中和川西北2个次级块体,巴颜喀拉块体可划分出东端的龙门山次级块体。深部探测反映出川滇和巴颜喀拉块体地壳中均存在着低速-高导层(体),它们是上地壳多震的原因之一。地质研究和现今GPS观测表明:各级块体均存在着SE向或SSE向平移运动、顺时针转动和隆升运动,但量值存在着一定差异。文中还给出了各主要活动断裂带的地质或GPS滑动速率,讨论了目前存在的主要科学问题。There exist several groups of seismogenic active faults at the conjoined areas of the Chuandian, Bayankala and Huanan active blocks along the eastern margin of the Qinghai-Tibetan Plateau. Owing to existence of transverse secondary active faults, the Chuandian Block can be further divided into the Middle Yunnan and Northwestern Sichuan sub-blocks, and the Longmenshan sub-block at the easternmost end of the Bayankala Block. Joint exploration of the crustal structure shows that low-velocity layers exist in the crust of the Chuandian and Bayankala Blocks. These low velocity layers correspond also to high conducting layers and they are the cause of frequent earthquake occurrence in the upper crust. Geologic study and GPS surveying indicate that the tectonic motion of the blocks in this region is accounted to be a complex or superimposition of three basic types of motions： southeastward sliding, rotating on vertical axis, and uplifting, but there is difference in the geologic slip rate and GPS rate. Besides, this paper collects the database of the geologic slip rates and GPS slip rates for the active faults in the region and major scientific problems are also discussed at last.

关 键 词：活动构造 活动块体 强震复发模型 川西 

分 类 号：P315.2[天文地球—地震学]