鄂东南—赣西北地区构造异常及其控制矿意义

鄂东南－赣西北成矿区是长江中下游区域地质异常场中的一个局部地质异常区,其内构造地质异常有多种类型。基底断裂交切点附近岩石破碎,岩浆侵位和热液蚀变强烈,构成控制中深部大岩基及其上部矿田的基底断裂异常。盖层构造中纵向断裂异常带是多期次构造复合和叠加的产物,滑脱拆离断裂异常带是伸展体制下层间与层内构造剥离的结果。二对于浅成和超浅成的小岩体侵位及其伴生矿床（体）的形态、产状和分布有明显控制作用。褶皱异常对某些含矿岩体和矿体也有一定的控制作用。岩石的孔隙（裂隙）度异常是岩石对含矿流体渗透性和储集性的集中表现,它是成矿流体迁移和矿质富集的重要条件。综合构造异常反映多种构造因素对成矿制约的一种综合性变量,它能清楚地显示出构造与矿床产状和定位的关系。

STRUCTURAL ANOMALY AND ITS SIGNIFICANCE IN CONTROLLING THE ORE DEPOSITS DISTRIBUTION IN SOUTH-EAST HUBEI AND NORTH-WEST JIANGXI PROVINCES

The metallogenic province in south-east Hubei and north-west Jiangxi provinces is one of local geological anomalies in Middle-Lower Yangtze regional geological anomaly field with various structural anomalies. The points and their surroundings where the basement faults intersect formed the basements fault anomalies in which rocks sharply were broken, magma activities and hydrothermal alteration were very frequent, and which controlled the large bulk of deep-seated batholiths and the ore fields above batholiths. In cover rock from Sinian system to Quaternary system, the longitudinal fault anomaly belts resulted from compounding and superimposing of multiple phases of structural deformation, and decollement fault anomaly belts occurred between or within rock layers by structural denuding under stretching mechanism, and they both evidently controlled the shape, occurrence and distribution of many small shallow-seated or supershallow-seated intrusive bodies and their associated deposits. Anomalies of porosity (fracture) of rock, one of important conditions for ore-bearing fluid to permeate through the host rock, are main channels for ore-bearing fluids moving and accumulating. Comprehensive structural anomaly, a kind of comprehensive variable expressing the various structural factors' effects on mineralization, can obviously indicate the relation among structure, the place and distribution of ore deposits.