| 华南金矿二元混合成矿模式 |
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| 引用本文：.1995.Binary ( deep and low ) mixed model of gold mineralization in south China[J].Mineral Deposits,14(1):1~11 |
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| 中文摘要:根据华南六个有代表性金矿的成矿时代、断裂构造、围岩、侵入岩、中基性岩墙，成矿类型、成矿阶段、矿石组成，成矿温度、包裹体成分以及稳定同位素等多方面研究，发现华南大部分金矿具有共同特征：主要成矿时代为燕山期，远落后于围岩时代；是沿地壳级大断裂形成的后生矿床；六个金矿的铅同位素组成均可分出高值区（组）和低值区（组），表明成矿物质有深浅两个不同来源；不同金矿氢、氧同位素指示成矿热液水为深源岩浆水与古大气降水两个来源水的混合。因此，华南金矿成矿物质和成矿热液水，既有通过地壳断裂来自深部下地壳或上地幔的，又有就地取材汲取上地壳古老变质围岩的，从而称为深浅二元混合成矿模式。 |
| 中文关键词:华南金矿 二元混合成矿 成矿模式 稳定同位素 |
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| Binary ( deep and low ) mixed model of gold mineralization in south China |
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| Abstract:In recent years, gold mining and prospecting have been developed rapidly in South China. The representative gold deposits, such as Hetai, Xinzhou, Nanchong, Longshui, Pangxidong and Baoban, are considered to be of different ages and genetic types. The genesis of the gold deposits is interpreted commonly by the polynary theory. According to country rocks, intrusions, intermediate-basic dikes, mineralization types, mineralization stages, ore mineral compositions, mineralization temperatures, fluid inclusion compositions and isotopic ages, however, we have found that they are mainly Yanshanian (100×l06～114×l06 a or 150×l06～180×l06 a) products and all belong to the same epigenetic mineralization type, formed much later than pre-Cambrian and Caledonian metamorphic country rocks and granites. The deep faults, which cut into lower crust or upper mantle and provided favorable channels for deep-source gold materials, frequently occur flanking these gold deposits. In the diagrams of 208Pb/204Pb versus 206Pb/204Pb and 207Pb/204Pb versus 206Pb/204Pb (101 data), the distribution of ore lead isotopes in these gold districts can be divided into the high value region (A, B, C, D, E and F) and the low region (A', B', C', D', E' and F').The high value region corresponds to the upper crustal metamorphic country rocks (W) of gold deposits, whereas the low corresponds to deep Yangtze series (Series II granites) (II).This shows that lead isotopes of these gold deposits were derived from two sources-one from upper crustal metamorphic rocks, and the other from deep sources, including Series II granites, intermediate-basic dikes, lower crust and upper mantle. In the diagram of δ18DH2O versusδ18OH2O, 138 data for these ore deposits fall mainly into the transitional area between the meteoric water line and the magmatic water district, suggesting that water of these hydrothermal gold deposits may be divided into two kinds: meteoric water and deep source water, including magmatic water. Therefore, although the gold deposits in South China appear very complicated in age and genetic type, they are actually rather simple and belong to the same epigenetic meso-epithermal type formed much later than country rocks. They are Yanshanian in age and their mineralization materials and water sources must have been derived from deep crust or upper mantle through deep faults, as well as from upper crust and paleometeoric water. So, the metallogenic model might be called binary (deep and low-source) mixed model of gold mineralization. |
| keywords:gold ore deposits in South China, binary mixed mineralization, metallogenic model, stable isotopes |
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