| 湖北浠水——梅川地区剪切带中金成矿作用 |
| |
| 引用本文： | 刘忠明,刘施民,蒋镇亚.湖北浠水——梅川地区剪切带中金成矿作用[J].大地构造与成矿学,2001,25(4):446-455. |
| |
| 作者姓名： | 刘忠明 刘施民 蒋镇亚 |
| |
| 作者单位： | 湖北省地质科学研究所, |
| |
| 基金项目： | 地矿部湖北地勘局科研项目，95 0225-16010064， |
| |
| 摘 要： | 作者分析了大量国内外金矿模式，并根据浠水－梅川地区的实际情况，提出金活化阶段、金初始富集阶段、金成矿阶段，并分别与韧性、韧脆性、脆性剪切变形相对应。成矿主要与脆性变形有关，韧性剪切变形向脆性剪切变形至关重要。从韧性剪切带向脆性剪切带转变的过程中，Ａｕ、Ａｇ、Ｃｕ、Ｐｂ发生大规模的活化迁移，并在较窄的脆性断裂中明显富集，形成矿体或矿化体。剪切带中的成矿流体在金矿形成过程中起着重要作用。随着变形机制、构造环境变化引起成矿流体沸腾作用并导致金矿形成。金矿成矿过程为：在挤压构造环境下，深层次韧性剪切带中形成原生富气相的（动力）变质流体；随着变质流体向上运移，温度逐渐降低，水蒸气开始逸出，液相成分增加，在伸展构造作用下，岩浆流体沿剪切带上升，不断改造和稀释着变质流体，最终形成以岩浆流体为主的成矿流体；随着伸展作用的继续进行，成矿流体静水压力不断降低引起流体沸腾，从而导致金矿形成。
|
| 关 键 词： | 浠水-梅川地区 剪切带 金成矿作用 |
| 文章编号： | 1001-1552(2001)04-446-10 |
| 修稿时间： | 2000年12月25日 |
GOLD MINERLATION OF SHEAR ZONES IN XISHUI-MEICHUAN AREA, HUBEI PROVINCE |
| |
| Abstract: | Analyzed many gold deposit models of inter and abroad, accorded to Xishui-Meichuan area, the authors put forward gold activation stage, first enrichment stage and ore-forming stage which respectively corresponded to shear strains of ductile, ductile-brittle, and brittle. Mineralization occurs at brittle strain stage. It is very important for the change from ductile to brittle shear strains. During the change, the elements Au, Ag, Cu, Pb activate and migrate on large-scale, and obviously enrich in narrow brittle faults, and form orebodies or mineralized bodies. Ore fluids in shear zones play a very important role during gold dc-posit formation. With the change of strain dynamic and tectonic situation, ore fluids boil and result the formation of gold deposit. The process of gold deposit formation is as follows: Under pressure situation, primary gas-rich(dynamic) metamorphic fluids are formed in deep ductile shear zone; As metamorphic fluids move upwards, temperature gradually reduces, water-vapor begins to escape upwards, liquid component increases. Under extensional tectonics, magnetic fluids go up along shear zones, continuously transform and dilute metamorphic fluids, causing the formation of ore fluids mainly made up of magnetic flutes at last. While extensionaltectonic is going on, fluids boil and gold ore bodies are formed as a result of continuous reduction of static-water pressure of ore fluids. |
| |
| Keywords: | Xishui-Meichuan area shear zone gold mineralization |
| 本文献已被 维普 万方数据 等数据库收录！ |
|
