| 华北地台北缘金矿成矿带的构造-水文特征 |
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| 引用本文：.1995.Tectonic-hydrologic characteristics of the gold metallogenic belt along the northern margin of north China platform[J].Mineral Deposits,14(4):335~345 |
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| 中文摘要:本文在矿石包体稳定同位素实测资料基础上编制了研究区成矿溶液δD等值线图，表明该成矿带内多数矿床在大气降水参与成矿过程方面具有整体性和统一性。计算各个成矿系统的水岩比后，根据其在δ18O-δD坐标系中的位置可发现：成矿带多数矿床分属3个构造-水文成矿系列——每个系列是由一组相对富岩浆水的成矿流体矿床为内核；一组相对贫岩浆水的矿床为外围围绕该核心。基于对各个成矿系统流体演化成熟度的计算，提出一种预测、评估矿床规模的构造-水文方法。 |
| 中文关键词:金矿成矿带 构造-水文特征 古地热系统 华北地台北缘 |
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| Tectonic-hydrologic characteristics of the gold metallogenic belt along the northern margin of north China platform |
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| Abstract:Lying 100～130°east longitude and 38～43°north latitude, the EW-trending gold metallogenic belt along the northern margin of North China platform, a belt 2000 km in length and 100 km in width, consists of more than one hundred hydrothermal gold-silver deposits. Wall rocks include Archean and Proterozoic mctamorphic rocks as well as Mesozoic granite and volcanic rocks. In the past, controversy existed concerning such ore-forming problems as hydrothermal types and metallogenic epochs of these ore deposits, and even of one deposit. Based on measured data of some 500 inclusions in ores from over 40 deposits, the author has compiled a deuterium contour map for the study area. The distribution of deuterium might be explained by Mesozoic paleogeography. It can be seen from the diagram that varied ore deposits show an integrity and unity in the ore-forming process of meteoric water. On the basis of calculated water-rock ratio of each ore-forming system and its position in the δ18O-δD coordinate , the author has found that ore deposits of this gold metallogenic belt might be divided into three metallogenic series, with each series composed of a core and a periphery, suggesting that ore deposits formed by ore fluids rich in magmatic water are located at the core, and lots of ore deposits formed by ore fluids deficient in magmatic water make up the periphery around the core. There seems to be regularity in the arrangement of the three metallogenic series: from the inland to the epicontinental area, ore-forming temperatures increase from 275℃ through 190℃ to 300℃, and metallogenic epochs change correspondingly from old to young, i.e. from J1+J2 to J3+K. As Blattner (1985) designed a method for hydrologic evolution of active geothermal system on the basis of isotopic (hydrogen, oxygen etc. ) drift, the author used hydrologic evolution to predict reserves of gold deposits which serve as the fossil geothermal system; as a result, some valuable results were obtained. In summary, the frame put forward by the author with the emphasis on hydrogeology enables geologists to understand individual ore deposits in the light of regional hydrogeology of the metallogenic belt as a whole. |
| keywords:gold metallogenic belt, tectonic-hydrologic characteristics, paleogeothermal system, northcrn margin of north China platform |
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