新疆艾肯达坂物化探综合异常的再解释

新疆和静县艾肯达坂39号铜矿点东南第四系大面积覆盖区存在1个物化探综合异常,多年来备受关注．2002年钻探查证后,对异常进行了再解释,查明了引起异常的原因．该高极化低电阻率激电异常是由下志留统依南里克组一套浅变质岩中的弱金矿化、弱石墨化、弱黄铁矿化碳质粉砂岩引起;低重力异常是由下志留统依南里克组中的次生石英岩、硅质岩和硅化大理岩引起;磁异常主要由厚达20m左右的下二叠统艾肯达坂组中基性火山岩砾石、岩块及碎屑等第四系堆积物引起,而下志留统依南里克组浅变质岩基本为无磁性岩石;全铜、有机铜和活动态铜异常主要是由第四系堆积物中大量铜矿转石和含铜高的中基性火山岩引起;壤中汞气和热释汞气异常是由断裂引起．证实了艾肯达坂物化探综合异常处于拉尔墩深大断裂带上．区域成矿地质条件对比表明,西南天山下志留统依南里克组一套浅变质岩具有形成“黑色岩系”型金矿的有利地质条件,是突破“库姆托尔式”金矿的有利地层,建议加强该区的金矿普查工作．

RE-INTERPRETATION ON GEOPHYSICAL GEOCHEMICAL ANOMALIES IN AIKANDABAN PASS IN XINJIANG

Geophysical anomalies with high apparent chargeability in the Quaternary cover of southeastern Aikengdaban Pass in Hejing county of Xinjiang have been known for many years.Prospecting by drilling on the anomalies revealed geological factors that led to a new explanation of the anomalies.It is shown that apparent chargeability anomalies are caused by a layer of carbonaceous siltstone with weak pyritization,the weak gravity anomaly is a result of silicifited marble and secondary quartzite in Yinanlik formation of lower Silurian system,the ordinary copper,organic copper and active copper anomalies are the result of cupreous volcanic rock blocks in the Quaternary sediments,and the mercury gas anomaly is derived from a regional deep fault.The weakly metamorphic rocks of Yinanlik formation of lower Silurian system is advantageous for "black rock type" gold deposits,such as the "Kumtor type" gold deposit.It is suggested that the prospecting for gold deposit in the region should be strengthened.