甘肃大水金矿微量元素地球化学特征及地球化学意义

Geochemical Characteristics and Geochemical Significance of the Trace Elements of Dashui Gold Deposit,Gansu Province

在分析甘肃大水金矿区域地质特征、矿床地质特征的基础上,结合该矿富矿岩石、贫矿岩石样本微量元素测试结果,对该矿床微量元素地球化学特征进行了详细研究,并对其地球化学意义进行了深入探讨。结果表明:1灰岩的Au含量较其他岩石高,金矿的形成与硅化有关,W、Ag与金矿床形成关系密切;2Sc、Ni、Cr、Ta含量表明该矿床的成矿物质来源于幔源,后期有壳源物质混入;3脉岩微量元素含量特征进一步证明该矿床的成矿物质在后期有元素的迁入和迁出,即成矿热液与上部岩石发生了混合岩化作用,在一定程度上反映了大水金矿的成矿机制,对于大水金矿的成矿理论研究具有重要意义。

Based on analyzing the regional geological characteristics and deposit geological characteristics of Dashui gold mining area in Gansu province,combing with the test results of the trace elements of the samples of the rich ore rocks and lean ore rocks of Dashui gold mining area,the geochemical characteristics of the trace elements of Dashui gold mining area are studied in detail,besides that the geochemical significance of the trace elements of Dashui gold mining area is also discussed in depth. The results show that: 1the Au contents of limestone is higher than other rocks,the formation of gold deposit is related to the silicide,W and Ag are closely associated with the formation of gold deposit in Dashui mining area; 2contents of Sc、Ni、Cr、Ta show that the metallogenic materials of the gold deposit are derived from the mantle source,the crust-derived material is mixed in the late of gold mineralization; 3the trace elements contents characteristics of the dike rock further show that some elements are immigrated and emigrated to the metallogenic material of the gold deposit in the late of gold mineralization,that is to say,the migmatization of metallogenic hydrothermal and upper rocks is conducted,which is indicated that the metallogenic mechanism of Dashui gold deposit,it is of great significance for the study of Dashui gold metallogenic theory.