中文摘要:龙门山铜矿为一赋存于月山岩体内部的矽卡岩矿床，由一个中等规模的透镜状矿体和多个小矿体群组成。成矿母岩属燕山早期石英闪长岩-闪长岩体，成矿围岩以中三叠统白云岩、膏盐层和下三叠统薄层灰岩为主。主要控矿构造有三种类型：①“舌状体”构造（主矿体控矿构造）；② 向斜构造（浅部围岩中顺层产出的小矿体控矿构造）；③ 压扭性构造裂隙（岩体中小矿脉控矿构造）。矿床的成矿作用分为三期六阶段和两个亚阶段，其中石英硫化物期的早硫化物阶段是主要成矿阶段。常见金属矿物共生组合有四组，代表了从氧化物阶段至表生期的成矿演化过程。成因类型为接触交代矽卡岩型富铜矿床。
Abstract:The Longmenshan copper deposit is of skarn type, its ore-forming wall rocks being Middle and Early Triassic limestone, dolomite, lime dolomite and calcic siltstcliif, and metallogenic parent rocks being early YanSliianian hypabyssal calc-alkaline-subakaline granodiorite-diorite, with the orebodies present both in xenolith-like skarns at the depth of the intrusive body and along the endo- and exocontact zone at small depth. The main orebody is a middle-sized one occurring at depth, which is lenticular in shape with localized expansion and ramification, being extremely unstable and having a thickness variation coefficient of Vm=123. Of all copper ore types, garnet skarn ore, scapolite skarn ore and magnetite ore are predominant. Metallic minerals comprise abundant chalcopyrite and bornite, moderate amounts of magnetite and hematite, and less molybdenite and skutterudite. As for gangue minerals, the commonly-seen ones include garnet: diopside, scapolite, albite, anhydrite, epidote, actinolite, quartz, calcite, K-feldspar and hydromica. The texture and structure are rioted for metasomatic and intercrystalline filling types. Copper is pretty high in content, but shows an uneven distribution, being frequently concentrated at convex or concave position and in the middle of ore bed. Orebodies at shallow depth are of small size, occurring in groups. According to their position of occurrence, they might be grouped into two types: (1) veinlike ones in intrusive body frequently arranged in feather shape; (2) lenticular orebodies occurring conformably in wall rocks, conditioned by structural styles. Ores are largely diorite type and brecciated marble type. In addition to the above mentioned copper minerals, considerable amounts of pyrite, molybdenite and copper oxides are observed. The gangue minerals are mostly calcite, dolomite and quartz. Ores contain relatively low copper, belonging to copper-poor type. Ore-controlling factors may be summarized as follows: (1) Intrusive body played its part: in metallization in such aspects as metallogenic time, space, exchange, differentiation and concentration of rock-forming and ore-forming materials. (2) Tongue-like structure, syncline at small depth and strutural fissures acted as ore-governing structures. (3): The role played by wall rocks finds expression in such, phenomena as variation in chemical composition of skarn, structure of ore, selected metasomatism and space occupied by orebodies. In addition, sulfur isotope determinations might be of referential value. Ore-controlling wall rocks are part of Middle and lower Triassic carbonate-evaporite formation. Metallization of the ore deposit might be divided into skarn period, quartz-sulfides period and hypergene period, in association with four groups of mineral assemblage, i.e., magnetite-hematite-pyrite, pyrite-chalcopyrite-bornite, pyrite -chalcopyrite-molybdenite and covellite-malachite-bitumen-like limonite. This deposit is genetically of contact metasomatic skarn type, with the ore materials supplied largely by the intrusive body and Middle Triassic clastic layer.
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陈锡昆.1987.龙门山铜矿床地质特征与成矿控制因素[J].矿床地质,6(4):43~52.1987.Geological Characteristics And Ore-Controlling Factors Of The Longmenshan Copper Deposit[J].Mineral Deposits6(4):43~52
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