| Anqing copper deposit is located in Yueshan town in Huaining county,Anqing city,Anhui province,which is one of the important copper deposits in the middle-lower Yangtze river metallogenic belt.After years of mining,shallow resource reserves in Anqing copper deposit are on the constant decline.Therefore,deep prospecting has become the focus of current geological work.The previous research reveal that the ore bodies in Yueshan area tend to occur in the plunging part and two limbs of folds.Besides,contact of Yueshan diorite and Yueshan Formation marble is necessary for mineralization.Fractures control spatial distribution and preservation conditions of the ore deposit.Two basement faults trend to NE and EW are good magma paths.Besides,NW and near SN faults were formed after mineralization and have destructive effect on the ore body.Therefore,study of folds and faults in this area is very important.In this thesis,we found the axis of main folds trend NNE by field stedies of folds in study area.The anticline plunging part,Yueshan-Huangtushan anticline,is favorable metallogenic area.F1 fault was formed after ore formation and ore body was destroyed by F1.It is found that F1 has the characteristics of repeated movements and mainly shows left-lateral displacement.The displacement of fault F1 is estimated to be about 200-400 meters and favorable prospecting target area is put forward.Controlled Source Audio-frequency MagnetoTellurics Method(CSAMT)is based on electrical differences between ore and surrounding rocks.It is found that low-resistivity zone caused by ore body in the CSAMT profiles.However,low-resistivity anomalies have multiple solutions,such as fault zone and aquiclude.Only CSAMT method is used done to guide the prospecting has uncertainties.In this thesis,we summarized the characteristics of CSAMT profiles curve which is "V"shape low-resistance belt and steep low-resistance belt in the adjacent regions found ore bodies.Through collecting 18 boreholes date and the measured data in WuZhujian exploration area and its adjacent area,superface contour maps of diorite rock masses and Yueshan stratum surface were made in WuZhujian exploration area.Then,we projected them to the CSAMT profiles and it is concluded that geological interpretation of CSAMT profiles.Besides,we found the curve characteristic of CSAMT profiles which are similar to adjacent area in contact zone of Yueshan diorite and carbonate rock.Therefore,favorable exploration boreholes were put forward.The Yueshan-Huangtishan anticline fold form was determined through field geological investigation.Zhuchong mine is located in its NW limb and Wuzhujian exploration area is located in its SE limb.An ore symmetric with Zhuchong ore body may exist in Wuzhujian exploration area through the structural analysis and favorable position of ore-bearing structure.Besides,two test boreholes acoording to CSAMT profiles were just located in the core and the SE limb of this anticline.Therefore,combination of geophysical data and structural analysis can improve the reliability of metallogenic target area prediction in deep prospecting. |
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