摘要
金川矿床产出于过渡区,位于中朝地块西南部阿拉善边缘隆起上,含矿岩体是多期上侵贯入形成的,时代为1508±31Ma。 导源于地幔深部富硫的铁质超基性岩浆,沿超壳深断裂上侵到达地壳岩浆房。注入岩浆房的岩浆发生熔离作用和岩浆分异作用,按重力效应在岩浆房中自下而上先后形成了矿浆、富矿岩浆、含矿岩浆和岩浆分层格局。随着温度下降,在构造应力脉动式驱动下,岩浆房中自上而下按岩浆、含矿岩浆、富矿岩浆和矿浆的顺序,先后分别沿相同通道上侵、贯入于现存空间成岩成矿、每次上侵、贯入的浆体都沿着前次浆体的下侧部和根部定位。 整个成矿过程由岩浆房中的深部熔离、岩浆分异和重力分层作用→第一期次岩浆上侵→第二期次含矿岩浆上侵→第三期次富矿岩浆贯入→晚期矿浆贯入→接触交代成矿→热液叠加成矿,构成一个完整的硫化铜、镍矿床的成矿模式和时空分布系列。
The Jinchuan deposit occurs in transitio regions. It is located in the Alashan uplift belt on the southwestern margin of the Sino-Korean landmass. The orebeari-ng rock bodies have been formed by intrusions and injections of magmas for many times. Its isotopic ages is 1508±31 Ma.
The sulfur-rich ferruginous ultrabasic magma derived from the deep-seated mantle was intruded in the magma chamber of the deep levels of the crust along the ultracrustal fault. The magma underwent liquid unmixing and olivine crystalization in the magma chamber between the liquidus line temperature and the solidus line temperature. Due to gravity effect, the early-separated liquid(unmixed sulphideme-1t) was then localized in the Lower part, while the later-separated liquid(unmixed su-1fide melt)together with the crystallized olivine were localized in the upper part, forming the stratified sulfide ore magma, sulfide-rich magma, sulfide-bearing magma andesilica-temagma upward in the magma chamber. As the temperature fell down, in process of the normal stress, these four types of magma ascend edseparately and successively along the same channel way down ward, and finally were consolidated at the present place. In every time, the injected and intruded magma was emplaced on the lower side or on the roof of the former magma bodies. The good growth of the sulfide-rich and crystal olivine-bearing magma and its orebody-forming injection indicate the main metallogenetic stage and minerogenetic climax stage.
The whole metallogenetic processes: deep seated magmatic liquid unmixing, crystalization of olivines and stratified action by gravity→the first stage silicate magma ascending→the second stage sulfide-bearing magma ascending→the third stage sulfide-rich magma injecting→late sulfide ore magma injecting→metasomatic min-erogenesis by contact→superimposed hydatogenesis, constitute an integrated minerogenetic model of copper nickle sulfide deposit and also a series of the temporal and spatial distribution
出处
《甘肃地质》
1991年第12期104-125,共22页
Gansu Geology
关键词
铜矿
镍矿
矿床
含铂
含硫
化合物
transition regions, deep steated magmatic liquid unmixing, intru-sion and injection for many times, hydatogenesis superposition, minerogenetic mode
