Comparative study of the geology and mineral resources in Xinjiang, China, and its adjacent regions

Abstract：This paper primarily summarizes the basic characteristics of the major metallogenic belts in Central Asia and discusses the possible extensions of the major metallogenic belts from the adjacent regions of Xinjiang to Xinjiang. With the constantly changing knowledge of the division of metallogenic belts and types and characteristics of metallogenic formations in adjacent regions of Xinjiang, the authors emphasize that in comparing the geology and mineral resources in Xinjiang with those in its adjacent regions it is necessary to gain knowledge of their research histories and seek to make such comparison based on ascertaining basic ore-controlling elements. In addition, in Central Asia mineralization related to Early Paleozoic continental crustal accretion is quite important, while Late Paleozoic large-scale mineralization is more markedly manifested by inheritance and reworking of pre-existing ore-forming material and superimposition of new ore-forming material, thus forming compounding of multi-stage mineralizations. All these belong to the characteristics of the Central Asian metallogenic megaprovince and must be fully considered in the comparative study. Analysis and comparative study in the paper suggest the following six metallogenic environments as the major factors controlling the formation of large and superlarge deposits in the Central Asian metallogenic megaprovince： 1) numerous Precambrian blocks in Phanerozoic orogenic belts, in which important primary uranium deposits and rare metal deposits are formed; 2) Early Paleozoic continental-margin accretionary wedge and late Caledonian eastern Kokchetav and northern Junggar (beyond the territory of China), where there occur important gold and copper polymetallic deposits; 3) the circum-Balkhash Lake region surrounded by Caledonia and pre-Caledonian continental crust, where ore-forming processes show several peaks and superimposition on each other or certain regular migration; 4) an important Au-Cu-Mo-W metallogenic belt in the southern part of the Central Tianshan (beyond the territory of China), which shows distinct linear features and is related to a huge hydrothermal system that was active for ~70 Ma; 5) the post-collisional intracontinental environment in South Kazakhstan and areas south of it, where most U deposits in Meso-Cenozoic basins and Late Paleozoic superlarge sandstone-type copper deposits were formed and their ore-forming materials probably have deep sources; and 6) sites of intersection between the so-called large-scale “transverse structures” and metallogenic belts, where most important deposits in Central Asia occur.