Characteristics And Forming Setting Analysis Of Gadaban Area Kuroko-type Deposit In Northern Qilian, Qinghai

North Qilian Qrogenic Belt is one of the more important cop per metallogenic belt in China, besides the sedimentary-hosted deposits of exhalation-Jingtieshan iron deposit, volcano-associated massive sulfide(VHMS or VMS) deposits is the main type in the area. Based on the mineralized tectonics, petrography and ore geochemistry, VHMS-type copper polymetallic deposits of Early Paleozoic in North Qilian divide the deposits into two types: one is “Cyprus-type” VHMS deposits related to the basic volcanic rock, mainly distributed in the volcanic rocks of the north Zoulangnanshang, represented by the Shijuli deposit, formation environment for the expansion of back-arc basin environment; another kind is “Kuroko-type” VHMS deposits related to acidic volcanic rock, mainly distributed in the western and eastern of the North Qilian Orogenic Belt, represented by the Baiyinchang and Gadaban deposits, ore-forming environment related to continental rift valley environment or arc tensile fracture environment. keep trying exploration Gadaban area of the North Qilian in recent years, Gadaban and Guomisi deposits have been found of medium size, that the two deposits in the region “Kuroko-type” ore deposit research has representative significance.The Kuroko-type massive sulfide deposits of the North Qilian Orogenic Belt are mainly distributed in the volcanic rock belts of the south Zoulangnanshangcorridor, are concentration distribution in Baiyingchang ore field and Gadaban ore field. The deposits of Gadaban ore field are with typical characteristics of the Kuroko-type massive sulfide deposits, ore deposits concentration distribution, layered, wall rock alteration phenomenon is obvious. These deposits main occurred in the acidic volcan ic rocks and basic volcanic rocks of the Daliugou-Bailiugou volcanic domeondome, strictly control the alteration belt. The deposits are containing hot water jet rock and its associated with the carbon black rock series, the rock assemblages are widespread in the hot water flow deposits, called a "double rock combination", is a typical sign of submarine hydrothermal sedex, and can be used as judgment an iconic rock combination of Kuroko-type massive sulfide deposits. Deposit ore-forming elements is given priority to with Pb, Zn, Cu, ore type of Zn- Pb- Cu and Pb- Zn- Cu, is Kuroko-type massive sulfide deposits; The temperature, salinity in the Gadaban ore field, comparative and study on the typical Kuroko-type ore deposit in the world, that conside the ore-forming fluid may be a mixture of magmatic hydrothermal and seawater in ore field.This paper collected the chemaical of volcanic rocks in the middle Cambrian Heicifgou group of Gadaban ore field, and testing the main elements, trace elements and rare earth elements of the rock samples. These test data and volcanic rock data were collected for analyzsis and research, should be the back-arc rift environment, to elucidating the marine-volcanic rocks about Kuroko-type ore metallogenic characteristics of mass ive sulfide deposits and prospecting prospect has guiding significance in the study area.