Preliminary Study On Regional Metallogenic Background And Metallogenic Regularity Of West Kunlun And Its Adjacent Area

The study area of West Kunlun and its adjacent areas located in Northwest Edge of Qinghai-Tibet Plateau crosses Tarim and South China Plate Tectonic Units. There are complete strata, various magmatic rocks and complex geological structures in the study area. In the point of view of mineralization domain, the study area lies in the contact zone of ancient Asia Metallogenic Domain, Qinling-Qilian-Kunlun Metallogenic Domain and Tethys Metallogenic Domain and its metallogenic geological condition is superior.According to the structures, sedimentary formations, magmatic formations and previous studies on the study area, tectonic unit division is discussed and the units are: Xikunbei Tectonic Unit, Xikunzhong Tectonic Unit, XiKunnan Tectonic Unit, Bayan Har Tectonic Unit and North Qiangtang-Tianshuihai Block.On the basis of systematic analysis of regional geological, geophysical and geochemical characteristics of the study area, 36 representative deposits (points) among 125 known deposits (points) have been selected. Ore-forming geological settings and deposit geological features are systematically discussed in different tectonic units.Directed by Theory of Metallogenic Series, regional metallogenic regularity of the study area is preliminarily studied by the combining of ore-bearing formation and structural environment. In accordance with the metallogenic characteristics of the deposits (points), they are classified by the genetic classification which includes ore deposit associations, deposit types and representative deposits. Ore Deposit association refers to the deposits which have different ages and different genetic types under the same tectonic setting. It is the foundation of Metallogenic Series'division and study. In this paper, the metal deposits in the study area are divided into three ore deposit associations : 1.Exhalation-Sedimentary ore deposits association related to regional extension; 2. Orogenic-type ore deposit association related to continental collision or inland subduction metallogeny ; 3. Exogenic ore deposit association related to the metallogeny of stable stages. These ore deposit associations are the products of different tectonic settings.According to regional metallogeny analysis and regional tectonic evolution, deposits in the study area are divided into 6 metallogenic series and 20 deposit types. The characteristic of time-space distribution of the deposits shows that regional metallogeny in different unit of the study area differs. The peak periods of regional metallogeny are Caledonain Tectonic- Metallogenic Cycle, Variscan Tectonic-Metallogenic Cycle and Yanshanian-Himalayan Tectonic-Metallogenic Cycle. Deposits are mainly distributed in the three tectonic units of Xikunbei, Bayan Har, North Qiangtang-Tianshuihai Block.Finally, conbined metallogenic geological background with characteristics of regional geochemistry and regional metallogeny, this paper puts forward 12 prospecting areas and provides a direction for further prospecting practice.