青海乌兰县托莫尔日特金矿区稳定同位素特征及其地质意义  

STABLE ISOTOPIC COMPOSITION AND ITS GEOLOGICAL SIGNIFICANCE IN TOMORITE GOLD DEPOSIT, WULAN COUNTY, QINGHAI PROVINCE

作　　者：张拴宏[1] 周显强[1] 田晓娟[1] 宋友贵[1] 

机构地区：[1]中国地质科学院地质力学研究所,北京100081

出　　处：《地质与勘探》2001年第5期10-14,共5页Geology and Exploration

基　　金：原地质矿产部定向科研项目 (地科定 97- 2 2 )

摘　　要：根据矿石及岩石S、H、O、Sr同位素组成 ,对青海省乌兰县托莫尔日特地区金矿床成矿物质来源及其成因进行了研究。结果表明 ,赋矿花岗质岩石 (主要为斜长花岗岩和闪长岩 )是深源成因的 (幔源或壳幔混合型 ) ,成矿物质主要来源于深部 ,而成矿热液主要来自周围的深源花岗质岩石 ,其性质为混合热液 (来源于岩浆热液 +大气降水 ) ,特别是在近地表处 ,有更多的大气降水参与了成矿。矿区内部分矿带的赋矿层位虽有所不同 ,但它们的稳定同位素特征却很相似 ,表明它们具有相同或相似的成因及成矿物质来源。Tomorite gold deposit in Qinghai province is located in NW and NWW-trending ductile-brittle shear zones. Study on the isotopic compositions of S, H, O and Sr in ores and wallrocks shows that plagiogranite and diorite in the area are all deep genesis(derived from the mantle or from the manthe-crust mix). The ore-forming materials came mainly from deep source. The ore-forming fluids mainly came from the deep genetic granitoid in the area, and some meteoric water was added into them during mineralization. Though the ore hosted by is different country rocks, their isotopic compositions have no great difference. The results show that ore belt in the area has same or similar genesis. The superposition localities of the ductile-brittle shear zones and deep genetic granitoid are the best positions for mineralization in the area. On the basis of the study, two positions for ore prospecting are given in this paper, and one of them has been proved by the field works in 1999.

关 键 词：成矿物质来源 稳定同位素 成矿预测 金矿床 青海 成矿热液 

分 类 号：P618.51[天文地球—矿床学] P597[天文地球—地质学]