【摘要】 甘肃阳山金矿带位于西秦岭南部,结合同位素测年资料发现阳山金矿区在侏罗纪早期、白垩纪早期及第三纪早期曾发生3期岩浆活动;稳定同位素分析结果显示,矿石中石英的流体包裹体δD值为-75‰~-56‰,1δ8OH2O为3.7‰~12.2‰,矿脉中黄铁矿及辉锑矿的3δ4S为-2.2‰~-0.7‰,表明阳山金矿成矿热液及成矿物质主要来自于岩浆作用;构造变形分析显示该区在三叠纪曾发生韧性变形,在侏罗纪早期产生韧—脆性变形;侏罗纪晚期以后区内构造转为脆性,早期以逆冲推覆构造为主,晚期主要为脆性伸展活动。结合该区地质构造演化史认为本区的3期岩浆活动与区域伸展作用有关,而与岩浆侵入有关的多期岩浆热液活动是促成阳山金矿床形成的主要因素。更多还原

【Abstract】 Yangshan gold deposit is located in Wenxian County, Gansu Province.Geochronology study shows that three magmatic-hydrothermal events happened in the ore district respectively in Early Jurassic,Early Cretaceous and Early Tertiary.Stable isotope analysis shows that δD value of fluid inclusions in mineralized quartz veinlet ranges from-75‰ to-56‰,δ¹⁸O_H2Ovalue ranges from 3.7‰ to 12.2‰,and δ³⁴S value of pyrite and stibnite ranges from-2.2‰ to-0.7‰,indicating that metallogenic materials and ore fluid are mainly from the magmatic events.Analysis of tectonic deformation indicates that ductile deformation occurred in Triassic Period,ductile-brittle deformation occurred in Early Jurassic,while brittle deformation occurred after Jurassic Period.The brittle deformation experienced early pression period and late tension period.By comparing the tectonic-magmatic events with the regional tectonic evolusion,we propose that the coupling of three magmatic-hydrothermal events affected by regional extension contributed to mineralization of Yangshan gold deposit.更多还原