Issues on China Regional Metallogeny

According to geotectonic evolution and regional lithospheric features, the authors proposed six metallogenic domains in China: (1) Tianshan Xingmeng metallogenic domain, (2) Tarim North China metallogenic domain, (3) Qinling Qilian Kunlun metallogenic domain, (4) Yangtze metallogenic domain, (5) South China metallogenic domain and (6) Himalaya Sanjiang metallogenic domain. In this paper, the authors also discuss, on the bases of geotectonic background and metallogenic evolutionary history, some metallogenic features of China: (1) A large percentage of ore formation occurred in paleo continental margins, including continental marginal rift and continental marginal accretionary orogenic belt. The majority of main mineral deposits are discovered on continental margins. (2) Superimposition of mineralization, favored the building up of giant and large mineral deposits, but often made the mineral deposits more complex in composition (associated components), morphology and structure. (3) Mineralization of crust derived anatectic granite is intensive and especially concentrated in the South China metallogenic domain. Mineralizations, including W, Sn and REE, are the products of long and mature development of W Sn polymetal rich earth crust in the metamorphic basement of South China Caledonian fold belt. (4) Epithermal ore forming system is well developed in the southwest part of Yangtze continental block. Ore deposits of Hg, Sb, As, Au, Ag and U densely occur in sedimentary strata of the Late Paleozoic to Triassic. Ge, Tl, Te can also constitute independent ore deposits. (5) Ore formation caused by tectonic dynamic activities is distinctive. Small scale continental blocks of China display intensive activities, which played a widespread and diverse role in ore control. Junctions of faults, synchronous faults, shear zone structure and metamorphic core complex are main ore control structures. (6) The gold mineralization is complex and diversified. The greenstone type gold ores in China were emplaced in the Mesozoic Yanshanian epoch after repeated mineralization and enrichment. As a result, the co product gold constituted 32 % of the gold output of China. (7) The mineralization is characterized by multiple stages and heterogeneity. The metallogenic epoch of China almost covers all geological periods. The general trend, the increase in intensity with time, culminates in Mesozoic Cenozoic and so do the varieties of ores and types of mineral deposits. (8) Ore mineralization culminated on continental margin in the Mesozoic, especially in the Yanshanian orogeny of the east part of China, resulting in the diversity of ores and intensive mineralization. These metallogeny features of China can be generalized as "composite continental metallogenic system".