Cheng Zhengpu12, Hu Xiangyun1, Li Ye1, Chen Yufeng1, Xu Shan1
1. Institute of Geophysics and Geomatics, China University of Geosciences(Wuhan), Wuhan, Hubei 430074, China;
2. Center for Hydrogeology and Environmental Geology Survey, CGS, Baoding, Hebei 071051, China
Abstract：We analyze deep conductivity structures based on MT data acquired at standard points(36°N84°E) in Minfeng Sag, southeast Tarim Basin, which is a part of SinoProbe project. First we process MT data with the Robust method, and then carry out polarization pattern recognition, static corrections, and 2D-approximator and induction arrow vector analysis. Finally, we conduct 2D inversion of two profiles with nonlinear conjugate gradient(NLCG). The inversion results show that the subsurface in Minfeng Sag possesses good electrical layered structures. According to the regional geological conditions, we conclude that the Moho depth is about 41 to 43km and 2 faults exist above the basement. Crustal structures of Minfeng Sag might be suitable for hydrocarbon accumulation based on crustal tectonic characteristic parameter calculation. Hydrocarbon source rock might be developed, but its maturity could not be high.
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