Research On Geological Feature And Metallogenic Condition Of Main Nonmetallic Mines Of The Yixian Formation In Western Liaoning Province

According to the basic principles of volcano pertrology and ore mineralogy, the paper expatiates on the main featuers of petrology and volcano cycle of Yixian Formation in vlocano basins of western Liaoning, and also discusses geological characteristics of perlite, zeolite and bentonite deposits. Finaly, the paper analysises the ore-controlling and metallogenic regularity of these deposits,and makes metallogenic prediction.Yixian Formation in western Liaoning can be divided into four eruption cycles, the fourth eruption cycle consists dominantly of intermediate-acid volcanic lava, pyroclastic rocks and sedimentary pyroclastic rocks. The intermediate-acid volcanic lava and pyroclastic rocks, which are rich in glassiness, are the main mineralization rocks of perlite, zeolite and bentonite. There are four deposit types of perlite, zeolite and bentonite, concluded molten magma type of the volcanic eruption, regenerative type of the volcanic lava, regenerative type of the ordinary pyroclastic rocks and regenerative type of sedimentary pyroclastic rocks. Volcanic facies is very important to the formation of perlite, zeolite and bentonite deposits. Perlite mainly occurred in volcano effusive and extrusive facies. Zeolite and bentonite are intimately associated with extrusive,explosive and eruption-depostion facies.Besides eruption cycles, volcanic facies, and mineralization rocks regional structure, volcanic apparatus and ore-forming medium are also the ore-controlling factors of perlite, zeolite and bentonite of Yixian Formation in western Liaoning.On the base of analyzing the forming process of zeolite and bentonite, the paper discusses the metallogenic regularity of perlite, zeolite and bentonite. And the studied region can be divided into 11 metallogenic prospect areas of perlite, zeolite and bentonite.