东天山镜儿泉铜镍矿床成矿预测及EH4地球物理测量依据

GEOPHSICAL PROSPECTING AND PROGNOSIS IN THE JINGERQUAN Cu-Ni DEPOSIT,EASTREN TIANSHAN MOUNTAINS

镜儿泉铜镍矿床产于东天山黄山-镜儿泉铜镍成矿带东部，是典型的岩浆熔离型铜镍硫化物矿床。岩体地质研究表明，基性-超基性葫芦岩体是一复式岩体，东部辉石岩相形成的小环切穿西部辉石岩相形成的大环，两环相交呈葫芦状。矿床形成受岩体控制，矿体呈似层状赋存于复式岩体西部辉石岩相的底部。EH4连续电导率成像仪测量结果清晰地反映了岩体的基本形态，识别了岩体的不同岩相：①超基性岩（1～300Ωm）在南北剖面呈不对称的盆状，东西剖面呈东浅西深相交的盆状，舍矿辉石岩相（130～300nm）呈盆状分布于橄榄岩相（1～130nm）外围；②中基性岩（500～1000Ωm）包括辉长岩相和闪长岩相呈漏斗状分布于辉石岩相外围，漏斗状形态预示岩浆上升通道可能在矿区西南部，在此基础上，预测葫芦岩体地下250～450m区段是最有希望的成矿区段。

Jingerquan deposit is a typical maonatic liquation Cu - Ni sulfide deposits, and located in the east part of the Huangshan - Jingerquan Cu - Ni ore bolt in the eastern Tianshan mountains. Basic - ultrabasic Hulu rock mass is a composite one that consists of the east small rock mass and the west larger one, and the former cut through the latter and shows a bottle gourd shape. The deposit was controlled by the basic -ultrabasic composite rock mass and bedded - like orebedies occurred in the bottom of pyroxenite facies of the west rock mass. EH4 electrical conductivity image system is used for measuring the sequence resistivity of the Hulu rock mass. The measured results can clearly identify the rock mass shape and different faces. Ultrabasic rock mass （ 1 - 300Ω· m） shows a basin in NS section, and two intersect basins in EW section, and smaller resistivity （ 130 - 300Ω· m） for the magmatic liquation Cu - Ni deposit, corresponding to mineralized altered pyroxenite facies, shows a basin around the peridotite facies（ 1 - 130Ω· m） in section. Basic rock mass including gabbro and diorite facies （500 - 1000Ω· m） displays a funnel shape and is distributed around the pyroxenite facies, and indicates a maona passage occurring in WS of the deposit area. Based on these, it is prospected that the area underground from 250m to 450m limited in the Hulu rock mass is a promising area.