胶东莱州新立金矿床深部三山岛断裂物化探异常特征及找矿靶区预测

Characteristics of Geophysical and Geochemical Anomalies and Prospecting Target Prediction Around the Sanshandao Fault in the Xinli Gold Deposit,Laizhou,Jiaodong Peninsula

三山岛断裂是胶东重要的控矿断裂,自三山岛北部海域至仓上地区,包括新立金矿床在内的多个金矿床受其控制。以往地质勘查资料显示,三山岛断裂在新立金矿床深部2000m以下仍有延深,但深部断裂及矿化蚀变带的形态及找矿靶区尚不清楚。本次选用区内典型剖面0勘探线的CSAMT测深、钻孔原生晕资料,结合已知地质资料综合研究认为,电阻率断面能够客观反映深部断裂带的展布规律,为推测蚀变带赋存形态提供了证据,矿体深部尾晕元素不发育、尾晕和前晕共存、呈反分带等轴向分带及叠加特征,指示深部仍存在盲矿体。本文运用综合物化探方法,综合研究莱州新立矿区深部三山岛断裂带赋存规律,预测一处深部找矿靶区,为今后该地区的深部金矿勘查工作提供参考。

The Sanshandao fault is an important ore controlling structure in Jiaodong.From the northern marine area of Sanshandao to the Cangshang area,many gold deposits including the Xinli gold district are controlled by this structure.Existing geological exploration data show that this fault extends downward over 2000m in the Xinli gold deposit,while the shape and prospecting target and mineralization alteration zone around the fault remain unclear.This work addresses these issues based on CSAMT sounding data and primary halo data of the borehole of No.0 exploration line,a typical profile,in this area.Combined with the comprehensive study of the known geological data,it is believed that the resistivity section can objectively reflect the distribution law of deep fault zone and provide evidence for the prediction of the occurrence form of alteration zone.The tail-halo elements do not develop in deep orebody,and the tail-halo and fore-halo coexist,showing the equiaxial zoning and superposition characteristics of reverse zoning,indicating the existence of blind orebody in deep.In this paper,comprehensive geophysical and geochemical exploration method is used to comprehensively study the occurrence law of deep Sanshandao fault zone in Xinli mining area of Laizhou,Jiaodong Peninsula and predict a deep ore prospecting target area,which provides a reference for the exploration of the deep gold deposits in the future.