摘要
合仁坪金矿床是湘西柳林汊金矿带最为典型的钠长石-石英脉型金矿床,本文对该矿方解石的碳、氧同位素组成进行了系统的研究。研究表明,方解石的δ13 CPDB值为-6.1‰^-3.9‰,δ18 OSMOW值为16.9‰~19.5‰,它们在δ13CPDB-δ18 OSMOW图上的范围介于原生碳酸盐岩、海相碳酸盐岩与沉积有机物之间,δ13C和δ18 O的值呈正相关关系,而且方解石流体包裹体的均一温度为210~240℃,盐度随着均一温度降低而降低,这是水/岩反应和温度降低耦合作用的结果,所以合仁坪金矿床成矿流体中的碳主要来源于赋矿围岩,水/岩反应导致围岩中碳酸盐溶解。另外,通过方解石的氧同位素求得的该矿流体的氧同位素组成为8.53‰~11.69‰,所以合仁坪金矿床成矿流体应该来源于变质水,属于低温变质热液。
The Herenping gold deposit, a typical albite--quartz lode gold deposit, is located in the Liulincha gold ore belt, western Hunan. The carbon and oxygen compositions of calcite are systematically studied in this paper. It is shown that the 313CpDB and the δ18OsMow of calcite range from --6.1‰ to --3.9‰ and from 16.9‰ to 19.5‰ respectively. In the δ13 CPDB - δ18 OsMow diagram, the hydrothermal calcite samples are all fall into the zone among igneous carbonate rocks, marine carbonate rocks and sedimentary organic materi- al. The homogenization temperatures of fluid inclusion in calcite vary from 210℃ to 240℃, respectively. The carbon and oxygen isotopic compositions of the calcite present a positive correlation, as well as the homogenization temperatures and salinities of fluid inclusion, which can best explained by calcite precipita-
出处
《有色矿冶》
2015年第3期4-8,共5页
Non-Ferrous Mining and Metallurgy
基金
国家自然科学基金项目(No41073036
41473043)
关键词
碳、氧同位素
碳酸盐岩
水/岩反应
溶解作用
合仁坪金矿床
carbon and oxygen isotope
carbonatite
fluid-- rock interaction
dissolution
Herenping gold deposit
