Characteristics Of The Typical Deposits And Mineralization Regularity, Chongyangping Area, Hunan Province

Chongyangping is located at the southeast edge of Jiangnan massif, the transitional belt of Yangtze massif and South China rift trough. It has experienced Xuefeng, Caledonia, Indosinian, Yanshanian and Himalayan crustal movements. The well developed strata, structures and strong magma activities create favorable regional geological environments for the formation of polymetallic deposits such as tungsten, tin and copper. To achieve a good result of prospecting, a package exploration is taken in this area(Chongyangping tungsten package exploration) recent years.This thesis work, On the basis of the former data gathered, the major work focused on the geological investigation and sample analysis for tungsten in Chongyangping. the following cognitions have been reached by the prospecting for the tungsten in this area.1. Through this work, good mineralized tungsten orebodies have been found near the contact zones of Indosinian granite in the working area. The sizes of the deposits are small, medium and large. This proves that the mineralization conditions are favorable in this area, and it also shows the potential that tungsten in south Hunan area can be formed in medium and large sizes not only in Yanshanian granite masses, but also in Indosinian granite masses.2. Through the study of this area, it is found the wall rock alteration has zonality. The alteration of the vein in horizontal direction(from inside to outside) and in vertical direction(from top to bottom) shows coincident changes: vein- greisenization – silicification- potash feldspathization- normal granite. The preliminary study shows that the early stage of the granite is rich in acid and alkali. With the change of temperature, pressure, etc., the alterations of potash feldspathization, silicification, greisenization, potash feldspathization, silicification and greisenization took place in order. During the alteration, the mineralized liquid gradually turned into acid environment from alkalic one, which led to the tungsten complex decomposed and finally deposited as deposits.3. Through this work, it is found that tungsten mineralization has many types: large quartz vein type wolframite and scheelite, small quartz vein zone type scheelite, skarn hornfels type scheelite, altered granite type scheelite, quartzite type scheelite and granite pegmatite type scheelite. Small quartz vein zone type is the major type in this area. By comparison, it is considered that the potential is existed to find quartz vein zone type scheelite and scarn hormfels type scheelite in the deep and in the surrounding areas of Lishanpo and Shanxi tungsten deposits inside Zhonghuashan rockmass, and to find skarn small quartz vein zone type scheelite in Chongyangping mass and Wawutang mass. Of the three masses, the surrounding areas of Zhonghuashan mass and Chongyongping mass have larger potential for prospecting, which can be the major targets for the next step of the package exploration.4. On the basis of knowing the geological background and deposits properties of Changyangping tungten deposits, and by the study of the mineralied geologcial conditions and mineralization, and by comparing the deposit properties of different masses, and combining different minerlized types and enrichment regularity, a preliminary prospecting model has been setup, which can be the guide and basis for future prospecting evaluation, prediction and exploration. It is also considered that this area has conditions to form medium and large tungsten deposits, and the surrounding and deep areas have good prospectiong potential.