论金川硫化铜镍矿床成因

ON THE GENESIS OF JINCHUAN COPPER-NICKEL SULFIDE DEPOSIT

本文在以往调查、勘探和综合研究的基础上,通过我国金川硫化铜镍矿床大量地质、地球化学资料的分析,论证了该矿床的成因。认为:1)该矿床的形成与多相熔体多次侵入,复合有关,第一、二次侵入是携带硫化物液滴和橄榄石晶粒的硅酸盐岩浆;第三次侵入的是运载大量榄榄石晶粒的硫化物矿浆;第四次侵入的是杂质很少的硫化物矿浆。2)各次所侵入的多相熔浆流之间具有密切的亲缘关系,它们是同一股含矿岩浆在过渡岩浆房中熔离—结晶—重力分异的产物。3)成矿母体为源自大陆地幔的含矿拉斑玄武质苦橄岩浆。4)成矿构造环境属克拉通区断裂带。

The paper discusses the genesis of Jinchuan copper-nickel sulfide deposit located in Gansu province, China, on the basis of a vast amount of geological and geochemical data. The main conclussions from this study are as follows:( 1 ) This deposit is considered to be formed by multiple intrusion of polyphase melts. What intruded for the first and second times were silicate magma carrying sulfide droplets and olivine grains ; the third time was su-Ifide ore magma carrying a great number of olivine grains;while the fourth time was sulfide ore magma only carrying a little impurity.( 2 ) All of the various polyphase melts were differentiate of the same ore-bearing magma in its interim-magma-chamber.( 3 ) The minerogenetic mother's body was ore-bearing tholeiitic picrite magma originated from the continental mantle.( 4 ) The tectonic setting of mineralization belongs to fracture zone in craton.