Study On Tungsten Mineralization In Fuling Area, South Of Anhui Province

Tungsten is one of national strategic mineral resources, which is also a current focu s on searching for minerals in China.The south of Anhui Province is the main prospectin g area of tungsten multi-metal in our country, and there is a great breakthrough in deposi ts of tungsten in the adjacent region of Northeast Jiangxi.Although we had made progre ss in the southern region, large and super large deposits remains need to be breakthroug h. And we should have in-depth understanding and research of deposit genesis and meta llogenic model, continue to carry out fundamental researches of the metallogenesis and metallogenic model etc. This paper relies on a project of China Geological Survey Bureau that" Tectono Magmatic Mineralization in Wannan Ningguo-Xiuning Area". On the basis of a systematical collection and a comprehensive understanding of the geological background of the region, this paper studied the mineralization of tungsten polymetallic deposit in Wannan Fuling area. All the comprehensively studying about the genesis of magmatite in the south of Fuling and the metallogeny of tungsten polymetallic deposits—are according to detailed field geological investigation and indoor analysis, combined with petrological and geochemical characteristics, isotopic geochronology, mineral geochemistry characteristics etc. And the main results obtained are as follows.1.The high-precision zircon U-Pb isotopic ages of two rock samples from Xiaoyao rocks dated are respectively 149.3+2.3 Ma (XY-01, a total of 13 points, MSWD=0.37) and 148.6+1.9 MA (XY-03, a total of 17 points,MSWD=0.48), which can be traced back to the late of Jurassic.2.SPetrological and geochemical analysis show that the amount of SiO2 in Xiaoyao rocks is 62.56wt.% - 68.95wt.%, and the one in Kaobeijian rocks is 64.93wt.%-65.97w.%. Besides, the alkali aluminum ratio (A/NK=A12O3/(K2O+ Na2O) of them is respectivly 1.24-1.70 and 1.59-1.73, andthe value of aluminum over saturation A/CNK (Al2O3/(CaO+K2O+Na2O) is between 0.96-1.01 and 0.88-1.04.Xiaoyao rocks and the Beikaojian rocks belong to high potassium calc alkaline series, I-type granite in Quasi Aluminum - weakly peraluminous systems and the granite porphyry in Xiwukou are A-type granite. These rocks are from the lower crust source area where the source in the mantle join.3.The process of crystal growth of the garnet includes fluid composition, acidity and redox intensity, which are dynamic changes without obvious trend of rising or falling. That is in the early of skarn stage, the physical and chemical conditions of contacting metasomatism are changing.Characteristics of the episodic changes of the girdle components, may be the results of its rebalance of chemical composition of fluid.4.The metallogenic period Xiaoyaowu polymetallic deposits, which are skarn type- tungsten polymetallic deposits, can be divided into early skarn rock stage, late skarn stage, oxide stage and sulfide stage etc.,;Xiwukou tungsten polymetallic deposits,which are quartz vein type-tungsten deposits, are mainly hosted in quartz veins, controlled by the secondary crack formed through deep fracture and granite porphyry.5.The genesis of Tungsten polymetallic ore payment in the south of Fuling is due to the anatexis of the area within the metamorphic fundamental rock series,through which formed deep magma chamber of granodiorite riched in W, Mo and Cu.The magma formed in the early Yanshanian age along structural fissures invade into the core of folds, and formed hypabyssal granite diorite and granite porphyry, with the characteristics that controlled by Fuling batholith.This paper enriched the understanding of the metallogenic regularity of Yanshan tungsten polymetallic deposits in Wannan area, and has certain practical significance for the follow-up prospecting of the tungsten and molybdenum polymetallic mineral exploration in Wanan area.