Study On The Minealization Relation Between Cu And Au Of Gaerqiong Mineral Deposit In Geji,Tibet

Gaerqiong deposit is located in the west of Gangdise metallogenic belt,adjacent to Shiquanhe Shenzha Jiali suture zone.It is a typical formed Cu Au deposit in the west of Gangdise metallogenic belt.Previous studies mainly focused on the geological characteristics,geophysical and chemical remote information characteristics,and geochemical characteristics of the deposit.The overall research degree is relatively low.The main ore-forming elements of the deposit are Cu and Au,and their mineralization characteristics and mutual relationship are mainly perceptual cognition supported by a small amount of rock ore identification,and these understandings are directly related to the determination of ore genesis and exploration direction,based on the project of "1 ? 50000 series map compilation for potential evaluation of Cu polymetallic deposits in the eastern section of Gangdise metallogenic belt" and "Research and delineation of resource concentration areas in Southwest China",and based on the hierarchical mineralization research idea of the tutor team,and this paper systematically and comprehensively studies the characteristics of ore-forming elements of Cu and Au and their relationship,and constrains the genesis and prospecting direction of the deposit,The main achievements are as follows:(1)The deposits are mainly disseminated,veinlets and stockwork,the main ore minerals are chalcopyrite,bornite,native copper,native gold which are hydrothermal minerals.The wall rock alteration includs skarnization,silicification and carbonation,which shows the characteristics of hydrothermal mineralization.(2)Grade A(associated grade ? boundary grade)is the main type of Cu mineralization,accounting for 74.58%,followed by grade B(boundary grade ? industrial grade),accounting for 21.04%,and grade C(industrial grade and above)is the least,accounting for 4.38%,which shows that the low-grade mineralization of Cu deposit is extensive,and the high-level mineralization is less.In the natural mineralized sections exposed by boreholes,the graded mineralization assemblages can be divided into three categories: single types,double types and triple types,including 7 subclass,with single types as the main type,accounting for 77.9%,double types taking the second place,accounting for 18.33%,and grade triple being the least,accounting for 3.77%;In each natural mineralized section,the classification structure types considering the relationship of graded mineralization can be divided into three categories: single grade,double types and triple types structure,including 20 subclass,with single-type structure as the main type,accounting for 43.39%,double types structure taking the second place,accounting for 37.09%,and the triple types being the least,accounting for 19.52%.(3)Grade A(associated grade ? boundary grade)is the main type of Au mineralization,accounting for 83.14%,followed by grade B(boundary grade ? industrial grade),accounting for 9.17%,and grade C(industrial grade and above)is the least,accounting for 7.69%,which shows that the low-grade mineralization of Cu deposit is extensive,and the high-level mineralization is less.In the natural mineralized sections exposed by boreholes,the graded mineralization assemblages can be divided into three categories: single types,double types and triple types,including 7 subclass,with single types as the main type,accounting for 88.5%,double types taking the second place,accounting for 7.37%,and grade triple being the least,accounting for 4.13%;In each natural mineralized section,the classification structure types considering the relationship of graded mineralization can be divided into three categories: single grade,double types and triple types structure,including 21 subclass,with single-type structure as the main type,accounting for 63.83%,double-types structure taking the second place,accounting for 22.55%,and the triple types being the least,accounting for 13.62%.(4)The structure types of samples(mineralization)reflecting the relationship between Cu and Au in a single sample can be divided into three categories: high Cu and low Au,Cu Au equivalent,Au high Cu low,including 14 subclass.High copper and low gold accounted for 49%,followed by Cu Au equivalent,accounting for 28.9%,the least is high Au and low Cu accounted for 22.09%.It shows that the ore-forming system of Cu and Au is obviously different;the structural types of Cu and Au segments,which reflect the relationship between Cu and Au mineralization,can be divided into two categories,i.e.Cu segment and Au segment,including 12 types.It reflects that different metallogenic hydrothermal systems related to Cu and Au mineralization occur isomorphic,quasi isomorphic and ectopic superimposition.(5)The geological characteristics of the deposit,graded mineralization of Cu and Au,classification combination,classification structure characteristics,sample structure and segment structure characteristics indicate that the Gaerqiong deposit is a Cu Au deposit with two major types and some subclasses of hydrothermal systems,which include appositive superposition and heterotopic superposition of copper and gold.(6)According to the regional extension trend of strong superimposition of ore-forming hydrothermal fluid reflected by the characteristics of Cu and Au graded mineralization plane and profile,a total of 10 border control targets and 3 deep bottom exploration targets are delineated,among which 7 are dominated by Cu-Au mineralization,3 are dominated by Cu mineralization,and 3 are dominated by Au mineralization,which provides a certain basis for the next exploration and prospecting work.