地震学报（英文版）2009，Vol.22Issue(4)：347-356,10.DOI:10.1007/s11589-009-0347-0
Crustal structure in Xiaojiang fault zone and its vicinity
Crustal structure in Xiaojiang fault zone and its vicinity
摘要
Abstract
Based on the integrative interpretation of travel-time data and amplitude information obtained from the deep seismic sounding experiment on the Chuxiong-Luoping profile, eastern Yunnan province, carried out in January of 2005, we present a 2-D P wave velocity structure along the profile. The crustal structure shows remarkable contrasts between the two sides of the Xiaojiang fault zone, although the whole profile is situated within the Yangtze platform. The average P wave ve-locities of the crust on the west and east sides of the fault zone are 6.21 km/s and 6.32 km/s, respectively, and the crustal thicknesses are 41 km and 45 km, respectively. These results imply that the crust to the east of the Xiaojiang fault zone pre-sents characteristics of crustal structure in a stable platform, while the crust to the west is complicated with a lower velocity zone in middle of the upper crust. The average velocity of 6.21 km/s is lower than the global continental crustal average (6.30 km/s), indicating that the region is teetonically active. According to the lateral variation of velocity and depth of inter-faces (including the Moho), it is inferred that the Xiaojiang fault zone has cut through the whole crust. It is also deduced that existence of low velocity zone in middle of the upper crust is conducive to the south-southeastern sliding of the Sichuan-Yunnan (Chuan-Dian) rhombus block.关键词
Xiaojiang fault zone/ crustal structure/ deep seismic sounding/ seismieity/ low velocity zoneKey words
Xiaojiang fault zone/ crustal structure/ deep seismic sounding/ seismieity/ low velocity zone分类
天文与地球科学引用本文复制引用
Chunyong Wang,Hai Lou,Xili Wang,Jiazheng Qin,Runhai Yang,Jinming Zhao..Crustal structure in Xiaojiang fault zone and its vicinity[J].地震学报（英文版）,2009,22(4):347-356,10.基金项目
This paper is supported by the project "Exploration of Active Seismic Faults in Large Cities and Earthquake risk Assessment" and Na- tional Natural Science Foundation of China (Grant No. 40774037). Contribution No. is 09FE3004 of Institute of Geophysics, China Earthquake Administration. （Grant No. 40774037）
