本文選題：地質(zhì)學(xué) + 磁黃鐵礦　； 參考：《礦床地質(zhì)》2017年02期

【摘要】：金川銅鎳硫化物礦床礦石類型主要為浸染狀礦石、海綿隕鐵狀礦石及塊狀礦石。采用礦相顯微鏡觀察、磁性膠體浸潤(rùn)與電子探針分析等方法,對(duì)3種類型礦石中磁黃鐵礦的結(jié)構(gòu)狀態(tài)、共生組合與成分特征作了研究,探討了礦石成因及成礦過程。在浸染狀礦石與海綿隕鐵狀礦石中,磁黃鐵礦為單純的六方(NC型)磁黃鐵礦,或者六方與單斜(4C型)磁黃鐵礦構(gòu)成的不規(guī)則狀交生體。這2類礦石中磁黃鐵礦的成因很可能是巖(礦)漿中S含量低,且高溫結(jié)晶后緩慢降溫,后期又受到了富硫和/或高氧逸度流體的交代作用。在Ⅱ礦區(qū)塊狀礦石中,單斜與六方磁黃鐵礦構(gòu)成平行葉片狀交生體,表明六方磁黃鐵礦在高溫下結(jié)晶后溫度曾快速下降,這期間僅出溶了微量的黃鐵礦,而當(dāng)溫度下降到254℃以下時(shí),發(fā)生了六方磁黃鐵礦中單斜磁黃鐵礦出溶作用。磁黃鐵礦的結(jié)晶類型、金屬原子(Fe、Ni、Cu、Co)與硫原子比值M/S演化等佐證了塊狀礦石晚期貫入成因。依據(jù)Fe-S系統(tǒng)相圖擬合曲線計(jì)算得到塊狀礦石中六方磁黃鐵礦結(jié)晶溫度為743~518℃,且在結(jié)晶過程中,硫逸度logf(S2)曾從0.427降至-3.767。
[Abstract]:The ore types of Jinchuan Cu-Ni sulfide deposit are mainly disseminated ore, sponge meteorite ore and block ore. The structural state, symbiotic assemblage and composition characteristics of pyrrhotite in three types of ores were studied by means of metallographic microscope, magnetic colloid infiltration and electron probe analysis, and the ore genesis and metallogenic process were discussed. In the disseminated ore and sponge meteorite ore, pyrrhotite is a simple hexagonal NC-type) pyrrhotite, or hexagonal and monocline 4C) pyrrhotite. The genesis of pyrrhotite in these two types of ores is probably due to the low S content in the rock (ore) slurry and the slow cooling after crystallization at high temperature, and the metasomatism of pyrrhotite by the fluid of rich sulfur and / or high oxygen fugacity in the later stage. The monoclinic and hexagonal pyrrhotite formed parallel vane intersecting bodies in block ore of mining area 鈪，

本文編號(hào)：1935672