Study On Types, Ore-controlling Factors And Prospecting Models Of Molybdenum Deposits In The West Part Of Henan

The west part of Henan Province, one of the important non-ferrous metal and noble metal ore concentrating areas in China, is especially rich in molybdenum ore resources. It is the largest molybdenum ore producing area in China and the second molybdenum ore belt in the world. In recent years, some super-large and large scaled molybdenum deposits such as Yuchiling molybdenum deposit have been discovered in the large magmatic batholith of this area. K-feldspar quartz vein typed molybdenum deposit, a new type of molybdenum deposit, has been discovered in magmatic rock of Xiong'er group in the study area.Through a large amount of field geological work, combining regional geological survey, typical deposit survey with experimental analysis, the results of prospecting works and research have been systematically studied in this paper. Porphyry molybdenum deposit and K-feldspar quartz vein typed molybdenum deposit have been studied a lot. It is concluded that porphyry molybdenum deposit is formed from magma differentiation and metasomatism while K-feldspar quartz vein typed molybdenum deposit is formed from hydrothermal fluid filling after volcanic stage. From the view of mineral prospecting, the types of molybdenum deposits have been reclassified according to the difference of occurring places of deposits. The molybdenum deposits in this area can be classified into four types, e.g. inner contact zone, contact zone, outer contact zone, and K-feldspar quartz vein type molybdenum deposits.In order to achieve evidences of the four types of molybdenum deposits mentioned above, the geological metallogenic background, deposit characteristics, metallogenic geophysical and geochemical characteristics, and deposit genesis have been deeply studied taking the Donggou, Nannihu, Leimen'gou, and Yuchiling molybdenum deposits and vein typed molybdenum deposits in Mt.Waifangshan areas as examples. Through the systematical study on petrological, mineralogical and geochemical characteristics of vein typed molybdenum deposits in Mt.Waifangshan areas, the concept of K-feldspar quartz vein typed molybdenum is firstly put forward, and the regional survey prospective of K-feldspar quartz vein typed molybdenum deposits has been also stated.Based on the study of regional metallogenic background and typical deposits, the ore-controlling factors of molybdenum deposit, such as the source of metallogenic material, metallogenic enviroment and mineralization, have been deeply studied. The new discovered K-feldspar quartz vein typed molybdenum deposits have been systematically discussed.Six types of prospecting indexes have been put forward, which are regional geophysics, geochemistry, strata, structure, magmatic rock and metallogenic epoch. Ore prospecting models corresponding to the four types of molybdenum deposits have been established. They are prospecting models of inner contact zone, contact zone, outer contact zone and K-feldspar quartz vein typed molybdenum deposits.Summarily, based on the classification of molybdenum deposit type, and study on ore-controlling factors, this paper sets up an ore prospecting model to guide the molybdenum deposit prospecting works of this area in the future.