云南富宁弄楼岩体岩相特征及成矿阶段划分

Longlou Rock Petrographic Characteristics and Division of Metallogenic Epoch and Stage of Mineralization of Funing in Yunnan

富宁弄楼岩体由边缘向中心依次为致密的辉绿岩相-中细粒橄榄辉长苏长岩相-细粒辉长苏长岩相-中细粒岗纹辉长岩相-中粗粒岗纹闪长岩相。基性-超基性岩浆岩是区内铜镍矿床的母岩,具有良好的分异现象。弄楼铜镍矿床中硅酸盐矿物主要为橄榄石、辉石,少量斜长石和角闪石,极少量的云母、方解石,金属硫化物为磁黄铁矿、镍黄铁矿、黄铜矿、磁铁矿,还含有少量的钛铁矿和方铅矿。结合矿石矿物组合及结构构造、矿体产出特征等研究,矿床形成主要经历了岩浆成矿期-构造-变质热液成矿期,而岩浆成矿期又分为早期岩浆熔离-结晶分异阶段-岩浆晚期成矿阶段-矿浆贯入成矿阶段-岩浆期后热液成矿阶段。矿床为岩浆熔离-结晶分异,后期热液叠加形成的矿床。

Funing rock mass from the edge to the center is the high density of diabase phase, a fine-grained olive gabbro norite facies, the middle fine-grained gabbro norite facies the middle fine-grained hillock grain gabbro phase, the middle coarse-grained in the gang wen diorite phase. The native rock of copper and nickel ore deposit in the studied area is consisted of basic - uhrabasic magmatie rock ,which has a good differentiation phenomenon. The sil- icate minerals in Nonglou copper nickel deposit are mainly olivine and pyroxene, a small amount of plagioclase and hornblende, very small amount of mica, calcite. The metal sulfides are pyrrhotite, pentlandite, chalcopyrite, magne- tite, also contains a small amount of ilmenite and galena. Combined with ore mineral combination and output struc- ture, orebody characteristics, ore deposit formation mainly experienced magmatic ore-forming period-structure-meta- morphic hydrothermal mineralization period, and magmatic ore-forming period is divided into early magmatic liqua- tion-crystallization differentiation stage-late magmatic metallogenic stages-ore pulp injection metallogenic stagesmagmatic ore-forming period after hydrothermal metallogenic stages. The form of deposit experienced from magmatic liquation-crystallization differentiation stage to the late hydrothermal superimposed period.