The Application Of Geophysical Prospecting On Maojingba Gold Deposit In Hebei

Hebei MaoJingba gold deposit is a typical tectonic altered rock type gold deposits,which has great potential mineralization ability.It is located in the FengNing-LongHuagold metallogenic belt in which distribution of dozens of small to medium size golddeposits locate. However, it exposes only one gold ore body in the surface.It is necessary touse geophysical technology in the surrounding areas for exploration of ore bodies,forlooking for unknown ore body in deep and surrounding areas to expand the gold reserves ofthe deposit.The known gold ore body locates in the altered mineralized fracture zone,the goldenrichment degree is higher where alteration and mineralization are greater.Gold generallyoccurs in pyrite, pyrrhotite, etc metal sulfide mineral in the ore.According to the physicalfeature of ore rock in the mine,the geophysical work take three kinds of geophysicalexploration technology such as high precision magnetic survey,the IP sounding method andsymmetric quadrupole.Through field measurements and indoor data processing,themagnetic susceptibility,electrical resistivity and chargeability plane contour map,flatprofile,profile,etc are drawn.Combined with the geology characteristics of this miningarea,as well as generally geophysical characteristics of the tectonic altered rock type golddeposits,on basis of the analysis4low to mediun resistivity and high polarization,highmagnetic susceptibility comprehensive abnormity are made out,which are concluded asgold.For the study the shape and depth of the possible gold ore body to provide technicalsupport for the subsequent drilling work,symmetrical quadrupole IP sounding are uesd inthe Ⅱabnormity and Ⅲ abnormity of work zone.It is clear by computer processing the IPsounding data,Ⅱ abnormal body corresponds two high chargeability lenticular body,bothare arranged echelon,the plane distribution is5~40m in width,10~200m in length,thetop boundary is buried4~5m in depth,down to400m;Ⅲ abnormal body corresponds twoparallel arrangement anomalies of high chargeability lenticular body,its plane distribution is30~80m in width,70~150m in length,the top boundary is buried18~20m indepth,down to220m.After the revealing project in line188,gold mineralization phenomenon are found in750point4meters underground, providing that the highpolarizability anomalies might be gold ore body or gold mineralization body.