Underground Structure And Metallogenic Model Study Of Zhaxikang Ore Concentration Area,in South Tibet

Through the collision between Indian and Asian plates,there are come into being a large-scale crust-mantle material interaction and a series of dome structure,also a large-scale mineralization.Zhaxikang polymetallic ore formed in such a background.We've got some idea about the metallogenic epoch and key controlling factor in this area.And those various geological information messages showed us that Zhaxikang deposit closely related to the Cuonadong complex rock mass.While there is too far to connect Zhaxikang deposit to Cuonadong,we need to find the underground connection between them.As the degree of geophysical study at this place is low,we designed MT,high-precision gravity and magnetic measurement works,trying to reveal the morphological characteristics of rock mass(the buried depth,tendency and so on)in this area.And provide geophysical evidences for the metallogenic model study by explaining the deep structural characteristics.Both MT inversion result and high-precision gravity and magnetic data find a hidden dome structure under Zhaxikang at a depth of 3km,which characterized by high resistivity,low density and weak magnetism in total.There is no visible magma conduit between the hidden dome structure and Cuonadong dome structure according to MT inversion graph.While high-precision gravity and magnetic data showed a remarkable path which connects the hidden dome structure with Cuonadong.Besides,gravity data show us a distinct response to the complex lithologic structure and a ‘S' type interface of Cuonadong and the hidden dome structure.The path connecting those two dome structures probably located at a depth of 7km on the west side,and 2km on the east side.In conclusion,we consider the low-density path as a fault fracture zone instead of a rock mass.We got the hidden connection of Zhaxikang and Cuonadong in the deep structure and the morphological characteristics of rock mass by geophysical methods.The results show that Zhaxikang deposit formed under the influence of dome structure strongly.It meaningfully fills a blank in the geophysical investigation in this area,also provides basic data in 3D modeling and deep prospecting work of Zhaxikang and Cuonadong at the same time.