Deep Structure And Prospecting Direction Of Zhaxikang Pb-Zn Polymetallic Deposit In Tibet

The Zhaxikang Pb-Zn polymetallic deposit is the most representative metal deposit in the Shannan region of Tibet.After years of exploration work,this deposit has become one of the super-large Pb-Zn polymetallic deposits discovered in Tibet,with the characteristics of large deposit size,high grade,steep ore body occurrence,and obvious mineral zoning.The research of Zhaxikang Pb-Zn polymetallic deposit has extremely important prospecting and theoretical guidance significance.The exploitable resources in Zhaxikang mining area are facing a crisis.Looking for deep mines and hidden mines has obviously become the key direction for prospecting in Zhaxikang mining area.The thesis takes Zhaxikang Pb-Zn polymetallic ore-concentration area as the research object,through field investigation and indoor data collection,systematically summarizing the metallogenic time and ore body characteristics and ore deposit geochemical characteristics of the typical deposits in Zhaxikang mining ore,Combining with rock physical properties analysis and the processing and interpretation of gravity and magnetic data,as upward extension and horizontal derivative and horizontal gradient modulus and vertical second derivative and 3d inversion,the fault structure grid of Zhaxikang Ore-concentration Area The framework and deep geological structure were reasonably inferred and interpreted,and three metallogenic prospects were delineated in the ore concentration area;and the geological structure in the deep part(0-5km)of the typical deposits in the Zhaxikang ore concentration area was focused,on the combination The metallogenic regularity of the concentration area puts forward the prospecting direction of the deep part of the typical deposit.Aiming at the important feature of ore-controlling fault structure in the mining area,from the perspective of gravity and magnetic identification,systematic sampling and physical property analysis of magmatic rocks and sedimentary rocks and metamorphic rocks in the Zhaxikang ore-concentration area are conducted.The results show that the rock density has good discrimination ability to the rocks and The rock Magnetic susceptibility has good discrimination ability to some rocks and poor discrimination ability to some rocks in the zhaxikang ore-concentration area.The deep geological structure of the ore-concentration area refers to the existence of hidden granite rock body deep in the ore-concentration area,which may be the same lithological intrusion with the leucogranite in Cuonadong,the difference between the two lies in the burial depth and emplacement,In the deep of the ore-concentrating area of different depths and positions of granite bodies buried form "branches" of different volumes.The fault-tectonic framework of the ore-concentration area means that the faults in the ore-concentration area are mainly near-north-south and near-east-west,including regional faults(F1,F2,F3,F4)and many secondary faults(represented by F5).Summarizing the deep geological structure and fracture structure framework of the known deposits,as well as the performance of gravity and magnetic anomalies,three deep structures and fracture structure frameworks,heavy and magnetic anomalies similar to the known deposits are delineated in the ore gathering area,The area is defined as three prospecting areas.In addition,we focused on dissecting the geological structure of 0-5km deep in the typical deposits of the ore-concentration area,combined with the metallogenic regularity of the Zhaxikang ore-concentration area,and proposed the prospecting direction of the deep part of the typical ore deposit,that is,Be-W-Sn and other rare metal ore bodies(mineralization)can be found in the the hidden granite rock body of contact zone inside and outside(3-2km deep in Zhaxikang mining area),Pb-Zn-Sb-Ag-Au and other metal ore bodies(mineralization)can be found away from the hidden granite rock body(2-0km deep in Zhaxikang mining area).