Sinistral shear and extension of the northern section of Lijiang Basin in northwest Yunnan in Quaternary  

作　　者：HANZhujun XIANGHongfa GUOShunmin 

机构地区：[1]InstituteofGeology,ChinaEarthquakeAdministration,Beijing100029,China

出　　处：《Chinese Science Bulletin》2005年第5期452-459,共8页

基　　金：supported by the Earthquake Science United Foundation(198023);the National Natural Science Foundation of China(Grant No.40272087).

摘　　要：The northern section of Lijiang Basin (NSLB) has the features of a zigzag fault, a kind of 'tracing extension' in the shape. Fault slip is characterized by both extension and sinistral shear. Average sinistral-shear and extensional displacements are respectively 1950 and 1730 m. This kind of movement began in middle Pleistocene, which is about 800 ka ago. Average sinistral and extensional slip-rates can be acquired, which are 2.44 and 2.16 mm/a. Geological evidence at different segments of the NSLB demonstrates results of geomorphic analysis, and is consistent with our knowledge about the zigzag fault. Realization of sinistral shear and extension of the NSLB provides direct evidence for the model of clockwise rotation of northwest Sichuan active block and the understanding of dynamic features of the Red River fault zone.The northern section of Lijiang Basin (NSLB) has the features of a zigzagfault, a kind of 'tracing extension' in the shape. Fault slip is characterized by both extension andsinistral shear. Average sinistral-shear and extensional displacements are respectively 1950 and1730 m. This kind of movement began in middle Pleistocene, which is about 800 ka ago. Averagesinistral and extensional slip-rates can be acquired, which are 2.44 and 2.16 mm/a. Geologicalevidence at different segments of the NSLB demonstrates results of geomorphic analysis, and isconsistent with our knowledge about the zigzag fault. Realization of sinistral shear and extensionof the NSLB provides direct evidence for the model of clockwise rotation of northwest Sichuan activeblock and the understanding of dynamic features of the Red River fault zone.

关 键 词：云南 丽江 曲折断层 红河 顺时针旋转 断层带 动力学 

分 类 号：P641[天文地球—地质矿产勘探] P343.1[天文地球—地质学]