| 试论中国铅锌矿床类型及其基本特征 |
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| 引用本文：.1983.A tentative discussion on types and main characteristics of lead-zinc ore deposits in China[J].Mineral Deposits,2(1):21~29 |
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| A tentative discussion on types and main characteristics of lead-zinc ore deposits in China |
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| Abstract:In order to raise the efficiency of ore-predicting and ore assessment, lead-zinc ore deposits of China have been classified in this paper into four main systems, twelve types and nineteen patterns. This classification proceeds from actual conditions of these deposits and takes into consideration comprehensively four essential factors: main sources of ore materials}ore-forming processes; major geologic factors governing ore-formation and economic value of the deposit. The following is a very brief summary of the main characteristics of the four ore systems: A. Ore deposits of hydrothermal system. Ores of this system are formed by the filling or replacement activities of hydrothermal solutions derived principally from crustal refusion and remelting migma. They develop in regions with overlying sedimentary strata of fold system bearing characteristics of miogeosyncline, and appear mostly in the vicinity of the contact zone between the intermediate-acidic granitoid and carbonate rocks mainly of Late Paleozoic era. Of these deposits, contact-replacement type is considered to have the highest economic value. It is mostly of large or medium size and rich in ore-metals, but rather complicated in form. B.Ore deposits of strata-bound system. Ores of this system develop along the rim of the paraplatform; their formation is ascribable to the sedimentation-transformation of eroded continental ore resources. They occur within some definite strata of the shallow-sea facies sedimentary formations belonging to the first period of both Early and Late Paleozoic era with seldom magmatic activities found in them. They are comparatively simple and stable, assuming stratiform or stratoid form. C. Ore deposits of volcanic system. They are formed by the action of volcanic hydrothermal solutions or volcanic sedimentation, the sources being the upper mantle magma. The deposits located in the fold system of the eugeosyncline occur mostly within the spilte-keratophyre format-on, whereas those located in the miogeosyncline occur mainly within the andesite formation of the continental volcanic series. D. Ore deposits of fracture system. Deposits of this system are formed by the lateral secretion filling, the material sources of which seem rather complicated. They are mostly found as veins within the crystalline folded basement regions. |
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