| 中国东部成矿域与成矿期的基本特征 |
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| 引用本文：.1982.The foundamental features of metalogenic megaprovince and epochs of eastern China[J].Mineral Deposits,1(1):1~14 |
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| The foundamental features of metalogenic megaprovince and epochs of eastern China |
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| Abstract:China has been metallogenetically separated into two preliminary.metallogenetic mega-provinces of different characteristics, i.e.the Western and the Eastern China megaprovinces with Yinchuan-Kunming deep fracture.as their separating boundary.ln the metallogenetic megaprovince of Eastern China, there are not only E-W to NWW trending foldbelts and fractures.but also N-S to NNE trending uplifts and depressions or parallel fault zones which make up configuration of tectonic frame called ccframe bone-structure. The NS, NNE tectonic sets are more or less parallel to the coast of the Pacific and it is therefore believed to be of affinity to Pacific tecto-nism, while the EW or NWW sets may represent compressed geosynclines, Marked with these compressed geosynclines the Eastern metallogeneticm,egaprovince is divided into three metallogenetic provinces with different metal-association, namely, from north to south as Northeast, Northhina and South China metallogenic provinces. Within each province, metallogenic belts, regions or clusters of different metals or deposit types are, in turn, subdivided. Temporally, there are apparently six major metallogenic epochs, i.e. (1) Archean banded iron ore of algornan type? ( 2 ) Proterozoic strata-bound copper and lead, zinc deposits; (3) Early Paleozoic marineexhalative pyritic copper. t/n, tungsten and copper deposits with affinity to granite, and copper-nickel deposits with affinity to basic rocks; (4) Late Paleozoic dominated with basic magmatism and its related ores. such as V-Ti-Fe, Cu-Ni, Cr, Pt and diamond, minor porphyry copper andmolybdenum deposits as well as skarn Fe, Cu, Pb, Zn, REE ores. (5) Mesozoic or the chief metallogenic epoch characterized by polymetallic mineralizations including W, Sn, Fe, Cu, Pb, Zn, Mo, Au, Bi, Sb, Hg, RE, etc. and some diamond; (6) Cenozoic metallogenic epoch of Au, Cu, Mo, RE and Se, Te, etc. Four remarkable features of Eastern China metallogenetic megaprovince are evident: (1) With the North China massif as axic, the mineralization of metal-association and deposit types show a kind of geometrical similarity southward and northward. First, on both southern and northern margins of the massif occur belts of similar Au-Mo (W) mineralizations. Further southward and northward there both appear geo-synclinal folded regions where Cu, Pb, Zn and Sn, W seem rather abundant. (2) Tentative application of the parameters to distinguish “I” and “S” granites in Eastern China metallogenetic megaprovince seems not well satisfied and ought to be modified. However, it does show a tendency that in the course of transformation from geosyncline to platform “S” type decreases while “I” type increases. (3) Metallogenic development usually spans intermittently a prolongable period but is still with some cyclical characters. Metallization in affinity either to granite or to basic rocks is examplified. (4) In Eastern China metallogenetic megaprovince, metallogenic element association seems closely related to tectonic layers of the crust. Rocks formed in different tectonic configuration appears to be of affinity to different metal-association, such as: Ultramafic: Cr, Ni, Co, Fe, Cu, Au, Pt, Os, Ir, Pd. Mafic: Cr, Ni, Fe, Co, Cu, Ti, V, Zn, Au, Pt. Acidic: W, Sn, Mo, Bi, Pb, Be, Sb, Hg, Ag, Nb, Ta, Zr, Ta, U, Li, F, As. |
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