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贵州锦丰(烂泥沟)金矿是滇黔桂“金三角”目前已探明的最大的卡林型金矿床。含砷黄铁矿是该矿床最主要的载金矿物,脉石英是最显著的热液蚀变作用产物。含砷黄铁矿、脉石英及其包裹体具有相同的稀土元素特征,表现为轻重稀土分馏明显(LREE/HREE:7.95～31.77,(La/Yb)_N:8.97～40.49);轻稀土有一定的分异((La/Sm)_N:3.20～5.29),曲线右倾程度大;重稀土分异不明显((Gd/Yb)_N:1.41～3.35),曲线平坦;负铕异常明显(δEu 0.59～0.71);微弱的铈负异常(δCe 0.97～0.98)。代表成矿流体特征的脉石英包裹体稀土配分型式及特征值与区域上不同时代的幔源基性-超基性岩差别较大,而与矿床围岩、矿石、含砷黄铁矿及其包裹体稀土配分型式及特征值十分相似,具上部地壳普通沉积岩的特点,反映成矿流体主要不是来源于地幔,而是以壳源为主。Eu负异常反映了偏酸性(富CO_2)、还原性的成矿环境;微弱的Ce负异常表明成矿流体来源于以沉积水和热脱水为主的盆地流体。
The Jinfeng (Lannigou) gold deposit in Guizhou is the largest Carlin-type gold deposit currently proven in Yunnan, Guizhou and Guangxi provinces and the “Golden Triangle”. Arsenic-bearing pyrite is the most important gold-bearing mineral in the deposit, and vein quartz is the most significant product of hydrothermal alteration. The arsenic-bearing pyrite, vein quartz and their inclusions have the same characteristics of rare earth elements, which are characterized by fractional light and heavy fractionation (LREE / HREE: 7.95-31.77, (La / Yb) _N: 8.97-40.49) ((La / Sm) _N: 3.20-5.29). The curves show a large degree of rightward slope, while the trace heavy rare earths are not distinct (Gd / Yb) _N: 1.41-3.35. ~ 0.71), weak negative CE (δCe 0.97 ~ 0.98). The REE patterns and eigenvalues of the vein-quartz inclusions, which represent the characteristics of ore-forming fluids, are quite different from the mantle-derived basic-ultramafic rocks of different epochs in the area, but are different from the ore-bearing rock, ore, arsenic-bearing pyrite The REE patterns and eigenvalues of the inclusions are very similar, with the characteristics of ordinary sedimentary rocks in the upper crust, which indicate that the ore-forming fluid is not mainly derived from the mantle but mainly from the crust. The negative Eu anomalies reflect the acidic (CO2-rich) and reductive metallogenic environment. The weak negative anomalies of Ce indicate that the ore-forming fluids originate from the basin fluids that are dominated by sedimentary and thermal dehydration.