The plastic deformation mechanism of Tankou salt mud uplift on the downthrow side of Qianbei fault and petroleum geological significance
Gong Xiaoxing1,2,3, She Xiaoyu2,3, Chen Jie, Xu Huiqun2,3, Tang Tingting2,3, Dong Zheng2,3
1. College of Energy Resources，Chengdu University of Technology，Chengdu 610059；
2. Hubei Cooperative Innovation Center of Unconventional Oil and Gas, Yangtze University, Wuhan 430100;
3. College of Geophysics and Petroleum Resource，Yangtze University，Wuhan 430100
The origin of Tankou salient on the downthrow side of Qianbei fault， Qianjiang depression， Jianghan Basin is one of the most attractive problems in this area. Based on the analyses of seismic profiles， it is considered that Tankou is a large scale salt mud uplift which formed by two sets of Yuyang Formatin—Xingouzui Formatin and Jingsha Formation—Qianjiang Formation multilayer salt mud up—diapir penetration， and the main formation stage is after the deposition of Jinghezhen Formation， the complete Qianjiang depression was divided into three sub—depression； The hanging and lower walls of Qianbei fault plastic lateral intruded upward extrusion and decollement—nappe north and south bi—directional compressive upwarp by differential loading and gravitational detachment dynamic effect， forming a three—layer structure： Salt mud uplift with taking the Hanshui fault plane as the base plate， salt mud uplift core in the middle and salt mud kink—faulted dome in the upper； Strong ductile deformation made the middle part of Qianbei fault plasticate—corrugate disappear， the upper segment sinistral turned into flat lying fault； The plastic deformation degree and morphological differences of each structural layers are relevant to the content of salt， gypsum， mud and the ration of salt， gypsum and mud； Salt mud uplift is the key factor in forming all kinds of reservoirs， the layers of the third section of Qianjiang Formation， upper of the fourth section of Qianjiang Formation and Xingouzui Formation lateral sealing by salt mud uplift and diapire， lithologic hydrocarbon reservoir have great potential in oil and gas exploration in this area.
Gong Xiaoxing,She Xiaoyu,Chen Jie et al. The plastic deformation mechanism of Tankou salt mud uplift on the downthrow side of Qianbei fault and petroleum geological significance[J]. Chinese Journal of Geology, 2016, 51(3): 920-933.