南秦岭北大巴山地区黑色岩系型钒钼矿床地质特征及成因

南秦岭与黑色岩系有关的钒钼矿床分布有南、北2个带,在北带山阳、商南一带分布有水沟钒矿床等一系列中大型矿床。近年来在南带镇坪县一带发现了唐家桠子钒钼矿床,研究认为南秦岭北大巴山地区黑色岩系中主要分布有K^1、K^2、K^3、K^4等4个含矿层,其中K^1、K^2含矿层发育于震旦纪陡山沱组(Z1d^1),K^3、K^4含矿层发育于下寒武统鲁家坪组(∈1l)。钒钼矿体总体呈层状、似层状产出,与地层围岩产状一致。含钒钼矿层的硅质岩、碳质泥岩、泥岩夹碳酸盐岩黑色岩系地球化学特征显示成矿物质来源与海底热水、生物沉积、陆缘碎屑等。矿床的形成与海底喷流热水沉积作用、生物沉积作用密切相关,钒钼矿体总体形成于深水-半深水缺氧的还原环境,矿床成因类型为沉积型。

Geological Features and Genesis of Vanadium Molybdenum Deposit of Black Rock Series in Northern Dabashan Area of South Qinling

There are two molybdenum-vanadium metallogenic belts of the black rock series in the south and the north of South Qinling.A series of medium-large deposits,such as Shuigou vanadium deposits,have been found in Shanyang and Shangnan in the north belt.In recent years,Tangjiayazi vanadium deposit has also been found in Zhenping county in the south belt.The study shows that 4 ore bearing strata of K^1,K^2,K^3,K^4 exist in the black rock series of northern Dabashan area in South Qinling.Among them,K^1 and K^2 developed in the Sinian Doushantuo group(Z1 d^1),and K^3 and K^4 in the lower Cambrian Lujiaping group(∈1l).Generally vanadium molybdenum ore bodies appear in bedded,near bedded,and being accordance to the strata.The black rock series of the siliceous rocks,carbonaceous mudstones and mudstones intercalated by carbonate rocks,which all bear the Vanadium molybdenum strata,indicate that the metallogenic materials were derived from submarine hot water sediments,biogenic sediments and terrigenous clasts,etc.The Genesis of deposits was closely related to submarine hydrothermal sedimentation and biological sedimentation.Vanadium molybdenum deposits generally formed in the anoxic reduction environment of deep and semi-deep water,the genetic type being sedimentary type.