LOW-TEMPERATURE THERMOCHRONOLOGY EVIDENCE FOR EXTENSIONAL MOVEMENT OF THE YI-SHU FAULT ZONE IN LATE EARLY CRETACEOUS
Wang Xianmei1, Zhong Dalai1, Wang Xuesong2, Lei Yongliang1, Gong Daohao1, Cheng Shuqi3
1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029; 2. Research Institute of Petroleum and Development of China, Beingjing 100083; 3. Yishui Earthquake Station, Linyi, Shandong 276400
The Yi-Shu fault zone(the Shandong sector of the Tan-Lu fault zone),could be divided into four faults,and named,in westward order,the Changyi-Dadian(F1),the Anqiu-Lüxian(F2),the Yishui-Tangtou(F3) and the Tangwu-Gegou(F4) faults.Six age data of apatite fission track(AFT),with samples collected from the profile across the F3,F4 and the Mesozoic basin sandwiched in between the both faults in northern part of the Yi-Shu fault zone,scattered from 102 Ma to 82 Ma and confined track length distributed between 13.0 and 14.0 μm.The inverse modeling resulted showed that there were two fast cooling episodes before 105～100 Ma and 85 Ma in uplift zone respectively.The AFT samples in basin underwent fast uplift during 85～60 Ma after it had been reached the deepest depth owing to fast sedimentation.After combining regional geology information and K-Ar age of two samples collected from the N-S-striking basaltic vein and the northwest-striking fault gouge near the Yi-Shu fault zone,the conclusions could be drawn that the Yi-Shu fault zone had been experienced two-stage evolution during Early Cretaceous: sinistral strike-slipping in early Early Cretaceous,and transtensional activation in late Early Cretaceous.Based on it,the related regional evolution in Crataceous was discussed in the paper.
Wang Xianmei,Zhong Dalai,Wang Xuesong et al. LOW-TEMPERATURE THERMOCHRONOLOGY EVIDENCE FOR EXTENSIONAL MOVEMENT OF THE YI-SHU FAULT ZONE IN LATE EARLY CRETACEOUS[J]. Chinese Journal of Geology, 2007, (4): 625-638,778.