Dextral strike-slip and tectonic transformation of the northern Longmen Shan fault belt from Late Neogene:A case study from the Qingchuan fault
Fan Chun1, Wang Erchie2, Wang Gang2, Wang Shifeng3
1. Key Laboratory of Marine Evolution and Hydrocarbon Accumulation Mechanism, Ministry of Education, China University of Geosciences, Beijing 100083; 2. State Key Laboratory of Lithosphere Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029; 3. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085
As an eastern boundary of the Qinghai-Tibetan plateau,the Longmen Shan fault belt devided the Songpan-Ganzi orogen from the Sichuan Basin on the Yangtze Block.A Study in the latest years have indicated that the middle and south segments of the Longmen Shan fault belt experienced right lateral shearing coeval with thrusting in Late Cenozoic time.The Qingchuan fault is an embranchment of the Longmen Mountain fault belt,we have found dextral strike-slip movement of the Qingchuan fault from field survey and remote sensing in Late Cenozoic.Many streams were offset along the fault,with a maximum of dextral offset being about 17 km.The Jiaoziding dome absorbed part of the offset at the southwest terminal,and the Hanzhong Basin absorbed most of the offset at the northeast terminal of the Qingchuan fault.Combined with strike-slip activities of the main fractures in the Qinghai-Tibetan plateau,the activity age of the Qingchuan fault was discussed.Furthermore,the mechanism for dextral strike-slipping of the Longmen Shan in Late Neogene was briefly explored in the paper.
Fan Chun,Wang Erchie,Wang Gang et al. Dextral strike-slip and tectonic transformation of the northern Longmen Shan fault belt from Late Neogene:A case study from the Qingchuan fault[J]. Chinese Journal of Geology, 2008, (3): 417-433.