Research On The Geological Characteristics And Genesis Model Of Jinchiling Gold Deposit

Zhaoyuan City, Shangdong Province, is the most important area in China for gold potential and gold production, and is honored the graceful name of Gold Capital.Starting from analyses of regional metallogenic background of Jinchiling gold deposit, the characteristics of geological geochemistry and the genesis of deposit, and the relationship between magmatic rock and mineralization in Jinchiling gold deposit are studied systematically and deeply by using the knowledge of petrology, structural geology, mineral deposit, isotope geochemistry, geochemistry of mineral deposits, etc. And more, the metallogenic regularities of Jinchiling gold deposit summarized is here.Based on the detail of geologic investigate, the author points out that there are eight kinds of dyke in the area. They are hornble nde-orthophyre,orthophyre,granodiorite-porphyre,diorite,lamprophyre,gra nite-porphyry,gabbro,and mineralize -granodiorite.Jinchiling gold deposit features small-scle gold ore bodies, densely-distributed occurrence and highly auriferous grade. The ore bodies are strictly controlled by NE- faults.The geochemical feature of the rare earth element of the country rock near orebody, magmatite and ore are studied systemactically, these reveale the geochemical action feature of rare earth element in the ore-forming process and diagenetic stage, and the main ore-forming element Au is derived from the source bed (Jiaodong group). The data of sulfur and lead isotopes show that sulfur and lead are derived from the deeper, the data of the compositions of gas and liquid phases in quartz, and calcite inclusion and hydrogen, oxygen isotopes suggest that ore-forming fluids is a mixture of magmatic hydrothermal fluids and meteoric water.The mechanism of mineralization in Jinchiling gold deposit is studied in detail. The author puts forward that the forming of the Jinchiling gold deposit is of the characteristics of multistage geotectonic evolution, multisource ore-forming materials, multiore-controlling factors, multimineralization, multigenesis typle. Controlled by the fault belt, the Jinchiling gold deposit is a polygenetic compound ore deposits which was formed in the granitization granite and reconstructed by mixed hydrothermal in Yanshan Epoch. And a related minerogenetic model has been set up.Through the analyses of ore-controlling factors, the conditions of the ore-bearing fault belt are put forward as follows: 1) it developed in the Linglong granitization granite which is came from Jiaodong group that is the source bed of the mining area; 2) it has a certain scale, which is over 1,000m along the strike and 500m along at the dip; 3 ) it should undergo multistage and multiphase movements, more movements number, easily formed multistage mineralization pile; 4 ) accompanying intrusion of the dykes, it made that the fault belt became the structural weak zone, which is favourable for the access and precipitation of the ore fluid; 5) it is the best for mineralization in fault of NE trending or NE turn to NNE or SN trending.Finally, the metallogenic regularities of the Jinchiling gold deposit have been summarized.