The Genetic Study Of Stratabound Sulfide Deposit In The Northern Ore Belt Of Wushan Copper Mine, Jiurui Area,Jiangxi Province

Wushan Copper Deposit is an important large deposit in the Fe–Cu–Au–Pb–Zn-sulfide–alunite–bentonite-gypsum metallogenic belt in the middle and lower reaches of Yangtze River.The study of its genesis and metallogenic regularity contributes to the deep prospecting practice.The Wushan Copper Mine is located in the middle of the Jiurui Mine Area,which is divided into two ore belts.Contact metasomatic skarn type ore bodies are developed in the southern ore belt,Stratabound skarn ore bodies and stratabound sulfide deposits are developed in the northern.This paper considers that stratabound sulfide deposits is a deposit of hydrothermal filling after the magma.Mineralization in the mining area is constrained by regional tectonic-magmatic.Mineralogical study shows that the main ore minerals of layered sulphide deposits are pyrite and chalcopyrite.The structure of pyrite are mainly colloidal structure,granular structure and dissolution structure.The chalcopyrite structure are mainly dissolution structure and metasomatic residual structure.The mineral tectonic mainly are vein structure,veinlet structure and sparse disseminated.colloidal pyrite does not have the typical characteristics of pseudomorphic substitution and microbial action.The mineral structure shows that the stratabound sulfide deposit has the characteristics of magmatic hydrothermal filling and metasomatism.Sulfur isotope test results:The?³⁴S value of colloidal pyrite is-0.49‰⁺4.10‰;The?³⁴S value of metamorphic pyrite is-0.78‰⁺3.76‰;The?³⁴S value of pyrite is-2.70‰⁺1.43‰;The?³⁴S value of pyrrhotite is+0.38‰;The?³⁴S value of chalcopyrite is-3.01‰^-0.36‰.The characteristics of mineral sulfur isotope composition in the study area indicate that the stratabound sulfide deposit in the Wushan North ore belt is affected by multi-stage magmatic hydrothermal action.The?³⁴S value of each mineral is consistent with the granodiorite porphyry body in the southern ore belt.The overall?³⁴S value is in the range of?³⁴S values of magmatic rocks,and has obvious characteristics of deep magmatic sulfur.The regional tectonic-magmatic system study shows that the Wushan copper deposit is located at the cross position of the north-north east fault and the northwest fault.Under the background of continuous thinning of regional crust,the deep magma rises in multiple stages along the“node”position of the regional fault transfer,causing the ore-bearing hydrothermal fluid to penetrate between the Huanglong formation and the Wutong formation"Slipline fault"ore storage space,filling the carbonate rock stratum of metasomatic roof and forming ore the stratabound sulfide deposits.