| Eastern Kunlun belt, one of most important noble-polymetal metallogenic belts in China, is located in the north margin of Qinghai-Tibet plateau, where there are lots of mineral resources. It was shown that Eastern Kunlun belt was a marginal orogenic belt with complex evolutional history and multi-stage marginal orogenesis according to studying to geodynamic evolutions of it and orogenic theories. This orogenic belt went through the following stages of evolutions, i.e. formation of Archean Paleo-continent, rift of Proterozoic Paleo-continent and formation of oceanic basalt plateau, closure of oceanic basin of Caledonian pre-tethys and amalgamative accretion between basalt plateau toward Qaidam block, late Hercynian-Indosinian Andes-type scissor-style amalgamative orogenesis, late Indosinian-Yanshanian lithosphere delamination and mantle-derived magma underplating, and Mesozoic-Cenozoic EW tectonic differentiation.It was considered that metallogenesis of gold deposits were consist with geodynamic evolution of Eastern Kunlun belt. Metallogenic epochs became newer southward while tectonic evolutions transferred southward. There are of multistage diplogenetic and anatectic natures. Gold deposits were related closely in genesis with extensive magmatic-structural motions in Hercynian era. Indosinian large scale of gold metallogenesis occured in the geodynamic settings, when lithosphere delamination, thinning, mantle-derived underplating and extensive crust-mantle interaction happened. C, H, O, S isotope researches shown that metallogenic materials came from upper mantle and strata, and the early stage of metallogenic fluid are major magmatic and formation water, then the late ones of it contained more meteoric water. With metallogenic temperature decreasing, metallogenesis were characterizaed by multistage evolutions.Gold-bearing strata consisted of Paleo-Proterozoic Jinshuikou group, middle-late Paleozoic Wangbaogou group, Triassic Bayan Har group and Naocangjiangou formation. Although the ages of ore-bearing strata were different, their formation accompanied with volcanic motions and turbidites by turbidity current deposit. Au, Sb, Hg(Au) deposits had similar geological and geochemical characteristics and genesises, which belong to typical orogenic gold deposits because their characteristics were similar to those of common orogenic gold deposits. The ore-bearing wall rocks reached (low) greenschist facies, and the rock types were major alteration types with minor quartz types. The contents of sulphide in them were low, from 2% to 7%. The most major, common and strong mineralizations consisted of those of pyrite and arsenopyrite. And alteration types were composed of major sericitization and carbonatization. Contrary to typical orogenic gold deposits at home and abroad, the orogenic gold deposits in Eastern Kunlun belt had many similar characteristics with those in other orogenic belts, and some exclusive natures.The deposits were controlled by ductile, brittle fault/fold systems. The ore-controlling structure types varied from epizonal brittle faults, to mesozonal ductile-brittle faults, and to hypozonal brittle-ductile faults.Geochemical researches of fluid inclusions shown that fluid inclusions, representing different metallogenic stages of quartzs in many gold deposits, could be divided into three types, that is CO2-enriched, CO2-H2O, and H2O ones. There were most H2O twophase fluid inclusions, which fluid systems consisted of H2O-CO2-NaCl-CH4±H2S±N2 and were of high CO2(≥5 mol%), low-middle temperature (118.8-459.3°C), low salinity (0.35-12.4%) and low density (0.54-1.00 g/m3). The fluid components shown that the metallogenesis happened in weak acid-middle neutral conditions.Isotopic dating shown that Indosinian was the major metallogenic stage for orogenic gold deposits in Eastern Kunlun belt. After subduction and closure of late hercynian-Indosinian Bayan Har oceanic plate, the magmatic and structural motions became strong. Then the following crust-mantle interactive events occurred, i.e. lithosphere delamination and underplating of mantle-derived magma. Lots of mantle-derived materials, energy took part in Indosinian metallogenesis, So Indosinian era became the most important hydrothermal metallogenic epochs, which had crucial meanings for large scale of mineralizations in Eastern Kunlun.According to the tectonic settings of Eastern Kunlun belt, geological characteristics, metallogenesis, genetic types, metallogenic epochs, spatial distribution laws of orogenic gold deposits in it, and same or similar inner relationships during metallogenic evolutions among Au, Sb, and Hg deposits, it was proposed that there was a orogenic gold metallogenic series, i.e. late hercynian-Indosinian orogenic gold metallogenic series. It was divided into three deposit models, including Dachang style, Dongdatan style and Kuhai style, on the basis of characteristics of these deposits, metallogenic elements and different metallogenic depths.Investigating typical gold deposits in Eastern Kunlun, and combining with deposit characteristics, metallogenesis, geochemical characteristics, metallogenic temperatures, pressures, and depths, the author built metallogenic models of typical gold deposits, and metallogenic models of orogenic gold deposits in it. While a crustal continuum model of orogenic gold deposits in Eastern Kunlun belt was proposed by the author, which consist of epizonal (Kuhai)→mesozonal-epizonal (Dachang, Dongdatan)→mesozonal-hypozonal (Kaihuangbei, Wulongou, Nachitai) orogenic gold deposits. It will have very important instructive meanings to do more assessment of mineral resources in the studying area according to the above-mentioned model.The author researched the metallogenic laws and assessed metallogenic (prospecting) potentials of gold deposits in Eastern Kunlun belt, while analyzing the postmetallogenic denudation and preservation conditions in it. Finally, 21 gold prospecting areas were delineated, using Expert Weights of Evidence calculating gold post probabilities. Then prospecting areas were classified into A, B, and C classes in turn of sums of post probabilities of every prospecting area, then major of them were simply assessed by the author.
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