PRELIMINARY STUDY ON THE GEOLOGY AND GENESIS OF THE JILINBAOLIGE SILVER POLYMETALLIC DEPOSIT IN INNER MONGOLIA

The Jilinbaolige silver polymetallic deposit in Dong Ujimqin Qi, Inner Mongolia, is tectonically located in the east of Early Paleozoic Chaganaobao-Aoyoute-Chaobuleng tectonic-magmatic belt on the southeastern margin of Siberian plate. The Upper Devonian Angeryinwula Formation is the main host stratum closely related to the silver polymetallic mineralization. The Jilinbaolige stock outcropping in the orefield, mainly composed of porphyritic monzogranite, is the supplier of ore-forming minerals. Fault structures are developed in the area, with NE striking tensional and E-W striking compressive fractures controlling the distribution of most silver polymetallic orebodies. With study on sulfur and lead isotope characteristics in Jilinbaolige silver polymetallic deposit, it is found that the sulfur in the silver polymetallic ores might come from the mixing and balancing effect of sediment sulfur and mantle or magma sulfur. The lead is mainly derived from the mantle and closely connected with the monzogranite outcropped in the orefield. Based on the comprehensive analysis on the geological and geochemical characteristics of the deposit, combined with study on regional tectonic evolution, it is concluded that the Jilinbaolige silver polymetallic deposit is related to the Variscan acidic -intermediate magmatic hydrothermal activities.