WANG Gang,
WEI Wen-Bo,
JIN Sheng et al
.2017.A study on the electrical structure of eastern Gangdese metallogenic belt.Chinese Journal Of Geophysics,60(8): 2993-3003,doi: 10.6038/cjg20170808
A study on the electrical structure of eastern Gangdese metallogenic belt
WANG Gang1, WEI Wen-Bo1,2, JIN Sheng1,2, ZHANG Le-Tian1, DONG Hao1, XIE Cheng-Liang1, GUO Ze-Qiu1
1. School of Geophysics and Information Technology, China University of Geosciences, Beijing 100083, China; 2. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China
Abstract：The famous Gangdese metallogenic belt hosts many large ore deposits within its eastern part. In order to examine the electrical structure of this region, the magnetotelluric data covering the main ore deposits were carefully processed and analyzed. A reliable electrical model was obtained using both two-dimensional and three-dimensional inversions. Combined with other geological and geophysical observations, our electrical model reveals that the ore deposits distribution can be interpreted as: (1) Ore deposits are located in electrical boundaries in the shallow crust. (2) The conductors observed in middle crust may have played a key role in the distribution of ore deposits, through buried north-south direction faults in the upper crust. (3) We propose that the intersection regions of north-south extensional structures and east-west thrust can be regarded as important metallogenic zones. (4) The lower crust may have been influenced by the asthenospheric upwelling and then became partially melted. The partially melted lower crust, together with the conductors in middle crust may have controlled the mineralization process in the upper crust.
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