滇西保山地块沙河厂矽卡岩型铜多金属矿床成矿物质来源和成矿过程

Study on alteration mineralization zoning, mineralization source and metallogenic process of skarn-type copper deposits in Shahechang in Baoshan Massif, western Yunnan

中文关键词: 沙河厂矿床  硫同位素  流体包裹体  成矿流体来源与演化  成矿机制

英文关键词: Shahechang deposits  sulfur isotope  fluid inclusion  source and evolution of ore-forming fluids  mineralization mechanism

中文摘要:

      沙河厂矽卡岩型铜多金属矿床位于保山地块中部，是近年来在北部核桃坪矿集区和南部芦子园矿集区之间发现的一个具有代表性的矽卡岩型矿床。本次研究在详细的野外地质调查基础上，对沙河厂矿床开展了矽卡岩矿物电子探针分析，流体包裹体激光拉曼和显微测温，以及硫同位素研究，揭示沙河厂铜多金属矿床的硫等成矿物质主要来源于隐伏的花岗质岩浆活动，且有少量地层硫的混入。成矿流体也起源于岩浆热液，演化过程中有大气降水持续混入。低温、低盐度的大气降水混入导致成矿流体温度降低可能是沙河厂矿床金属沉淀成矿的关键控制因素。沙河厂矿床矿成矿期次、成矿物质和成矿流体来源等方面所获得的研究成果对于深入理解保山地块区域成矿规律，指导区域下一步找矿勘查工作具有重要意义。

英文摘要:

      The Shahechang skarn copper polymetallic deposit, located in the middle part of the Baoshan block,is a representative skarn deposit discovered in recent years between the northern Hetaoping ore concentration areaand the southern Luziyuan ore concentration area. Based on detailed field investigation, this study carried out elec-tron probe analysis of skarn minerals, laser Raman and microscopic temperature measurement of fluid inclusions,and sulfur isotope studies on the Shahechang deposit, revealing that the ore-forming sulfur in the Shahechang cop-per polymetallic deposit mainly originated from Concealed granitic magmatic activities, with a small amount ofstratigraphic sulfur mixed in. The ore-forming fluid also originated from magmatic hydrothermal fluids, and mete-oric water continuously mix in during the evolution processes. The temperature decrease of ore-forming fluidscaused by the mixture of low-temperature and low-salinity meteoric water is probably the critical controlling factorof metal precipitation and mineralization in Shahechang deposit. The research results are important for the under-standing of regional metallogenic law of the Baoshan block and guiding the further exploration in this region.