Analysis On Geochemical Characteristics And Prospecting Of Northwest Area Of Angren County,Tibet

The northwestern region of Angren County,Tibet,located in the hinterland of south central Tibet and the northern foot of the Himalayas,belongs to the Cuoqin-Xurucuo iron-copper metallogenic belt which attached to the Gangdese metallogenic belt.The study area has experienced strong tectonic deformation,frequent magmatic activity,providing a good ore-forming geological background.In the recent years,several important deposits are found in and around the research area,revealing tthat the research area is an idea prospect target with great potential..Except for small-scale geochemical survey,the research degree of mineral exploration and basic geologyin the research area,especially on the mineralization regularity and mineral resource potential,is low..Combing the basic geological and mineral data,this study focuses on the geochemical data of stream sediments survey in the area,and uses a variety of exploration methods and research methods,to study the ore-forming geological regularities and make ore-forming predictions.Based on the geological background and the analysis of geochemical data of 1: 50,000 stream sediments survey in the study area,Zn,Ag,W,Pb,and Mo are considered as the main metallogenic elements,and the Laga Formation,Angjie Formation,and Suona Lake Formation are the main ore-forming layers in the study area.There are 262 single element anomalies and 125 main mineralization anomalies: 19 gold anomalies,18 arsenic anomalies,9 silver anomalies,12 antimony anomalies,22 mercury anomalies,10 tungsten anomalies,11 lead anomalies,11 zinc anomalies,8 bismuth anomalies and 5 beryllium anomalies.Besides,there are 36 combinations of anomalies delineated,with the mainly three combinations of tungsten-beryllium-uranium,gold-antimony,lead-zinc-silver.9 comprehensive anomalies that are well integrated with various types of anomalies in geology,mineral exploration,geochemical exploration,and remote sensing are delineated.Three comprehensive anomalies,including Adanri,Xiaka Village,and Pugu,have been evaluated.Finally,the ore-controlling geological factors in the area are analyzed,and the ore-search signs are summarized to indicate the ore-search direction.Based on the geological and mineral data,three grade ? metallogenic prospect area,all of which are categorized as B-type.Based on the division of the grade ? metallogenic prospect,three prospective target areas are further delineated,all of which are categorized as B-type prospective target area..The comprehensive application of soil geochemical profile survey,1:10,000 geological survey,trough exploration,soil stripping and other work,found three ore spots : Adangri lead-zinc ore spotwith 3 mineralized veins(2 lead-zinc mineralized veinsand1 lead mineralized vein);Xiakacun village molybdenum – rhenium-rubidium ore spot with 14 mineralized veins;Pugu molybdenum-niobium-thorium ore spot with 2 mineralized veins(1 niobium-thorium rare-metal mineralized veins and one molybdenum mineralized vein),further verifying the reliability of the delineated prospective areas.