Left-lateral shear deformation found in southern part of the Gaoligong range in west Yunnan and its tectonic implications

It is generally understood that the Tertiary structural deformation in the Gaoligong range in west Yunnan was under the control of right-lateral shear, resulting from the northward movement of Indian relative to Eurasian. In the southern part of Gaoligong range, however, we have recently found many pieces of evidence of left-lateral shear deformation, featuring a 10 km wide shear zone cutting through all tectonic elements of the range in N-S direction, which possibly occurred in late Tertiary time, and postdated the right-lateral shear. This is a significant discovery for revealing characteristics of the Tertiary intracontinental deformation of the Gaoligong range and the interaction between the Indian and the Eurasian continents.     

Left-lateral shear deformation found in southern part of the Gaoligong range in west Yunnan and its tectonic implications

LocatedinthesouthwestborderareaofChina ,theGaoligongrangeisauniquegeologicandgeomor phologicfeature ,withitssnow cappedsummitele vatedupto 35 88mabovesealevel.ItgoesupnorthalongtheNuRivertoeasternTibet ,joiningupwiththeBoshulalingrange ,anddownsouthtotheareaofLongling ,whereitdescendsrapidlyandsplitsupintoseverallowandlinearridges .RespectivelytothewestandeastoftherangearetheTengchongandBaoshanblocks ,themainpartofwhich ,anarrowbeltofin tensivelydeformedmetamorphicrocksnamedGaoligongGroup …