Abstract:Jiangxi Province striides across two geotectonic units, i. e., the South China fold system and the Yangtze paraplatform. With the exception of volcanogenic deposits, all tin deposits consisting of seven types can be found in this province, of which the economically important ones are the quartz vein type, the cassiterite-sulphide skarn type, the greisen type and the Quaternary placer tin. Stratigraphy is an important geological condition for mineralization. Of all the tin reserves established to date in this province, over 50％ are in Cambrian and 4 5％ in Sinian, with some of the comercial tin deposits also found in Devonian and pre-Cambrian strata. Cambrian and Sinian may be the source beds for tin mineralization in that they have significantly high tin content(2.7 and 2.6 times respectively the content of the average sedimentary rocks given by Vinogradov). The carbonate-silicious formation in north Jiangxi seems to be a tin-bearing source bed, where the geochemical fields are characterized by Cu, Mo, Pb, Zn, Au, Ag, W and Sn association. In south Jiangxi, however, the metamorphosed sialic clastic rock formation may be the source bed, and the regional geochemical fields are marked by the general enrichment in the associalion of W, Sn, Bi, Mo, Li, Nb, Ta, etc. The major tin deposits in this province are concentratedly distributed in the South China Fold System, at the margins of both Yangtze Paxaplatform and Jingnan Anteclise, and in downwarping fracture zones within the paraplat form and the anteolise. Controlled by the axes of regional anticlinoria and the upwarping zones, there occur in the whole province four E-W(ENE) striking tin belts and three NE(NNE)striking ones. The intersections of these belts are the favorable positions for the formation of tin ore fields. Compounding positions of the axes of brachy-anticlines with the E-W(ENE), NE, NNE and NW striking compressor tenso-shear fractures are the major structures controlling the tin deposits(ore bodies or ore veins). Tin mineralizations are all linked with tin-bearing medium-to fine-grained biotite granites or their autometamorphic products, the tin-bearing two mica(or muscovite)granites. These ore-related granites generally occur as plutonic, Shallow-eroded minor stocks or as the protruding parts of batholiths, characterized by their richness in topaz and zircon. In petrochemical composition, they belong to normal Pacific type calc-alkaline magmatic series; in trace element contents, they are of the W, Sn, Bi, Mo, Be, Li, Nb and Ta association type; REE distribution pattern of the granites shows a great negative anomaly in Eu, while initial 87Sr/86Sr ratio is commonly greater than 0.7100 (that of the Zengjialong tin-bearing biotite granite is equal to 0.7324). Genetically, these tin-bearing granites belong to the crustal remelted granitoid type. Tin deposits in this province have gone through a relatively prolonged metallogenic history: source beds of tin ore and source rocks of tin-bearing magmas were formed during or prior to Paleozoie Era; in Mesozoic times, accompanying the intense tectonic movement which took place in Indo-sinian and Yenshanian orogenios, activities of the remelted tin-bearing granitic magmas culminated in intensity and extension. Consequently, the period of magmatism and mineralization concentrated within 193-104 Ma before the present. Such a period occurred slightly earlier in the south than in the North of Jiaugxi. In South Jiangxi, prospecting for quartz-vein type wolframite-cassiterite deposits should be further carried on; in North Jiangxi, full attention should be paid to cassiterite-salphide skarn deposits; in Wuyishan-ttuaiyushan area of east Jiaagxi, due weight ought to be given to prospecting for greisen type, pegmatite type,porphyry type and volcanogenic type tin deposits; whereas in the whole province, it is essential to study the metallogeny of pre-Yenshanian granites, the tin-bearing nature of Paleozoic intermediate to ultra-basic voIcanic rocks and the related polygenetie composite stratiform tin deposits.
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周耀华，王发宁，虞长富.1985.江西锡矿床的区域成矿地质特征[J].矿床地质,4(4):25~34.1985.Regional metallogenic-geological characteristics of tin deposits in Jiangxi province[J].Mineral Deposits4(4):25~34
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