摘要
为了研究康滇地轴中段会理县黎溪地区层状铜矿的成矿机制,选取了典型的黎溪式铜矿—汪家湾铜矿床作为研究对象,通过对矿床岩石主微量元素、H-O-S同位素测试结合成矿流体特征,分析矿床沉积环境和成矿物质来源并总结其成矿机制。综合研究显示,矿床沉积时水深较浅,沉积物以白云石为主,次为盐类矿物并含少量泥质,沉积环境为高温还原环境的咸化泻湖。矿床中硫同位素组成变化较大,δ^(34)S值为-2.62‰~9.00‰,平均3.20‰,推测硫来源为海水硫酸盐和深部地幔。δD(V-SMOW)值分布于-65.0‰~-73.7‰,δ^(18)O_(H_(2)O)值在4.84‰~9.44‰,说明包裹体中水有建造水、变质水和岩浆水。矿床沉积阶段以热化学反应成矿为主,后期随着更高温度的热液岩浆对矿床进行改造,形成了后期局部富集的浸染状和团块状矿体。因此,汪家湾铜矿属沉积-改造型矿床。
In order to study the metallogenic mechanism of the layered copper deposits in the Lixi area in Huili county in the middle of the Xikang Yunnan axisthe typical Lixi-style copper deposit-Wangjiawan copper deposit was selected as the research object.Through the tests of major and trace elements of the deposit rocks and H-O-S isotopes combined with the characteristics of ore-forming fluids,the sedimentary environment of the deposit and the source of ore-forming materials were analyzed and the mineralization mechanism was summarized.Comprehensive research shows that when the deposit was deposited,the water depth was relatively shallow,and the sediment was mainly dolomite,followed by salt minerals and a small amount of argillaceous matter.The sedimentary environment was a saltwater lagoon in a high-temperature reducing environment.The sulfur isotope composition in the deposit varies greatly,withδ^(34)S values ranging from-2.62 to 9.00‰,averaging 3.20‰.It is speculated that the sources of sulfur are seawater sulfate and the deep mantle.TheδD(-SMOW)values range from-65.0‰to-73.7‰,and theδ^(18)O_(H2O)values are from 4.84‰to 9.44‰,indicating that the water in the inclusions includes construction water,metamorphic water and magmatic water.The sedimentary stage of the deposit is mainly characterized by thermochemical demineralization.In the later stage,with the transformation of the deposit by hydrothermal magma at higher temperatures,the formation of locally enriched infectious and cluster-like ore bodies in the later period was achieved.The Wangjiawan copper Mine belongs to the sedimental-remodeling type deposit.
作者
何明龙
胡杰
普琼
扎西顿珠
HE Minglong;HU Jie;PU Qiong;ZHA XI Dun-zhu(Regional Geological Survey Team,BGEEMRSP,Chengdu 610213;The Sixth Geological Team of the Bureau of Geology and Mineral Resources Exploration and Development of the Tibet,Lhasa,Xizang 850000)
出处
《四川地质学报》
2025年第3期472-478,483,共8页
Acta Geologica Sichuan
基金
受地球深部探测与矿产资源勘查国家科技重大专项(2024ZD1002100)
四川省地质勘查基金项目“四川省会理汪家湾铜矿普查”(编号:DZ202203)资助。
关键词
地球化学特征
成矿机制
H-O-S同位素
沉积-改造型铜矿
康滇地轴
黎溪式铜矿
geochemical characteristics
metallogenic mechanism
H-O-S isotope
sedimentation-transformation type copper deposit
Xikang Yunnan axis
Lixi-style copper mine
