GENESIS AND METALLOGENIC MODEL OF GUILAIZHUANG GOLD DEPOSIT
Lin Jingqian;Tan Dongjuan;Yu Xuefeng;Xu Wenliang;Li Bingren;Li Ying(Changchun Univ.of Earth Science.Changchun 130026);(Second Feam of Geology and Mineral Resources Bureau of Shandong Province.Yanzhou 272000)
Several types of gold mineralization were gathered in and around the Tonshi subvolcanic complex characterized in K-rich alkali affinity.In the framework of mineralization model,the Guilaizhuang gold deposit is related to intrusion cryptoexplosion breccia.Breccia type and porphyry type of gold mineralization were distributed in deeper layer.The telescoped minerali zation of gold was formed in the iron-ore bearing skarn belt.The types of layer-like and vein-like gold mineralization were generated at the bed of Mantou group upon the monzonite porphyry sill.Many Kinds of metallic minerals,such as native gold,electrum,telluride minerals and sulphide minerals are disseminated in the ore body.The grade of gold is 7.54×10￣(-6)in average and variates in a wide range. The ratio of Ag/Au is 1.3 in average. There is a tendency of Au enrichment at a shallow level of the ore budy with low temperature. The gold deposits in Guilaizhuang belong to a type of alkalic-related,precious-metal rich,quartz fluorite-adularia,hypabyssal and low-to-moderate temperature hydrothermal deposit.