Research On The3D Spatial Distribution Of Alteration And Elements And The Metallogenic Regularity In Yaojialing Zn-Au-Polymetallic Deposit

Much exploration work has been done for a long time and the regional geologicalresearch level is becoming higher and higher, how to accelerate the achievement ofprospecting breakthrough is a significant strategic task in recent years. With the rapiddevelopment of computer visualization techniques, how to use the technology to thegeological field reasonably has drawn more and more attention of geologists.Yaojialing Zn-Au-polymetallic deposit，located on the eastern edge of Tongling oredistrict, is a recently-discovered large zinc-gold deposit in the Middle-Lower reaches ofYangtze River, and the mineralization of Yaojialing Zn-Au-polymetallic deposit mainlydistributes in the permian limestone xenoliths and the contact zone of limestone andgranodiorite porphyry. Many researches should be encouraged and it is beneficial forrevealing the metallogeny of it, significant of all, some results could reveal a favorableprospect for searching similar deposit in transitional area.Based on the fund project:"the geological survey project of China Geological Survey:the geological deepth survey of the middle segment in the Middle and Lower Yangtzemetallogenic belt " and the the three-dimensional (3D) modeling technology, baesd onthe spatial distribution of alteration and mineralization elements in YaojialingZn-Au-polymetallic deposit as the research subjects, it extracts the geologicalinformation from the relevant geological data and quantifies it, then builds acomprehensive geological database of the ore deposit with the Surpac software. And onthis basis, this paper also builds3D geological body solid model, alteration block modeland elements grade block model of the ore deposit. This paper identifies the majoralteration of the deposit into six types: silicification, kaolinization, potassic alteration,chloritization, carbonatization and skarnization, and the main metallogenic elementsinto six types: Cu, Pb, Zn, Au, Ag and S. In addition, this paper draws plane andsectional contour maps about the alteration and mineralization information with theSurfer software.Through a comprehensive analysis of these models and maps from thethree-dimensional space perspective, the main results of this paper finally obtained asfollows:(1) The3D geological body (surface, stratum, ore body and rock mass) solid models,alteration block model and elements grade block model of the ore deposit has been built;the contour maps about alteration and mineralization elements of plane and someimportant sections in this deposit have been drawn. (2) With a comprehensive analysis of the results of the3D distribution of alterationand metallogenic elements, some conclusions include below: the Pb-Zn-Agmineralization concentrates in the shallow location of the contact zone betweengranodiorite porphyry and limestone xenoliths, and the Pb-Zn-Ag mineralizationassociated with alteration by relevance in descending order: kaolinization>chloritization> carbonation> silicification> potassic alteration> skarnization; while theCu-Au mineralization concentrated in the body and the lower part of the limestonexenoliths and granodiorite porphyry contact zone near the long, and the Cu-Aumineralization associated with alteration by relevance descending order:skarnization>potassic alteration> carbonation> chloritization> silicification>kaolinization.