Late Quaternary normal faulting and its kinematic mechanism of eastern piedmont fault of the Haba-Yulong Snow Mountains in northwestern Yunnan, China  

作　　者：WU ZhongHai ZHANG YongShuang HU DaoGong ZHAO XiTao YE PeiSheng 

机构地区：[1]Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China [2]Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China

出　　处：《Science China Earth Sciences》2009年第10期1470-1484,共15页中国科学（地球科学英文版）

基　　金：Supported by Department of International Cooperation of Ministry of Science and Technology of China (Grant No. 2006DFA21320);China Geological Survey of Ministry of Land and Resources (Grant No. 1212010541404);National Natural Science Foundation of China (Grant No. 40501006)

摘　　要：The regional geologic and geomorphic observations show that an active arcuate normal fault constitutes the main boundary fault of the Haba-Yulong Snow Mountains (HYSM). This fault is called eastern piedmont fault of Haba-Yulong Snow Mountains (HYPF). The fault consists of two segments with differential trend; the northern segment is NW-trending and NE-dipping and the southern section is S-N trending and E-dipping. Three sets of fault scarps cutting late Quaternary landforms and their dating results indicate that the fault is a prominent Holocene active fault and its throw rates are 0.3―1.4 mm/a during late Quaternary. The geometry and kinematics of the fault suggest that the arcuate normal faulting or rifting are typical surface deformation pattern at the two tips of the Z-shaped rift zone of northwestern Yunnan, which is related to regional east-west extension accompanying clockwise rota- tion of micro-block.The regional geologic and geomorphic observations show that an active arcuate normal fault constitutes the main boundary fault of the Haba-Yulong Snow Mountains (HYSM). This fault is called eastern piedmont fault of Haba-Yulong Snow Mountains (HYPF). The fault consists of two segments with differential trend; the northern segment is NW-trending and NE-dipping and the southern section is S-N trending and E-dipping. Three sets of fault scarps cutting late Quaternary landforms and their dating results indicate that the fault is a prominent Holocene active fault and its throw rates are 0.3–1.4 mm/a during late Quaternary. The geometry and kinematics of the fault suggest that the arcuate normal faulting or rifting are typical surface deformation pattern at the two tips of the Z-shaped rift zone of northwestern Yunnan, which is related to regional east-west extension accompanying clockwise rotation of micro-block.

关 键 词：NORTHWESTERN Yunnan the Haba-Yulong SNOW MOUNTAINS QUATERNARY normal FAULTING blocks rotation 

分 类 号：P542[天文地球—构造地质学]