山西省高凡银金矿床的成因

GENESIS OF GAOFAN SILVER-GOLD DEPOSIT IN SHANXI PROVINCE

产于五台花岗岩—绿岩带上部高碳质浊积岩系中的高凡银金矿床,与燕山期火山—次火山复式岩体有空间联系。本文通过多方面的研究,探讨了矿床的物质来源及其与多种地质因素的成因联系。

Gaofan silver-gold deposit is hosted by carbonaceous turbidite sequences, occuring in the upper ofWutai Archean granitoid-greenstone belt. In the orefield, there are Yanshanian volcanic-subvolcanicintermediate-acidic magmatic rocks whose genesis is closely realted to the granitoid-greenstone belt. The gold contents in turbidite and the volcanic-subvolcanic complex are not uniform, very highin carbonaceous phyillite and the alteration zone of the complex, although their mean basicaly coincidewith that of the same kind rock in the world. Carbon in ore and CH_4 in gas component of fluid inclu-sions in quartz tested very high. Some organic inclusions were found. The range of δ^(34)S Values(-5.4～+3.5‰) are relatively narrow. The δD values(-86.5～-64.4‰) and δ^(18)O values(+2.63～+12.65‰) indicate that ore-foming fluid mainly originated from the magmatic water. The δ^(18)O and δ^(13)Cvalues of carbornate in ore are similar to those in the strata, which consistent whith oceangenetic car-bornate. The composition of Pb-isotope, whose model-ages range from 926--1089Ma, have the featureof ancient anomalous lead. All of the above characters suggest that the carbonaceous turbidite and the volcanic-subvolcaniccomplex jointiy play important roles in the process of mineralition. So this deposit is a regeneratedturbidite-hosted deposit in the Archean greenstone belt.