安徽繁昌盆地南缘构造特征与控矿规律研究

Relationship between structures and their controls to ores in the southern margin of Fanchang Basin in Anhui Province

繁昌盆地作为长江中下游成矿带的重要组成部分,与特提斯、太平洋两大构造体制的转换密切相关,是研究中国东部中生代构造-盆地-岩浆-成矿内在联系和时-空关系的天然实验室。繁昌盆地南缘位于长江中下游转换构造结内,具有三级构造控矿特征:①铜陵-南陵断裂带是一级控矿构造,是区内多金属矿床的导矿构造和储矿构造;②燕山期叠加褶皱是二级控矿构造,控制着成矿热液的运移和就位;③含矿地质体是三级控矿构造,是良好的导矿和储矿空间。印支期和燕山期构造活动为姚家岭多金属矿成矿流体运移提供了良好的通道和就位空间:①导岩构造主要是铜陵-南陵大型断裂带;②导矿构造包括铜陵-南陵破碎带、构造透镜体间的空隙带、含矿透镜体内的褶皱岩层面、层间破碎带、平行褶皱枢纽的裂隙等;③储矿构造主要为含矿透镜体的上下边界、透镜体内的褶皱岩层面、层间破碎带、平行褶皱枢纽裂隙等。

As an important part of the Middle and Lower Yangtze River metallogenic belt, the Fanchang Basin is closely related to the transition from the Tethyan Tectonic Domain to the Pacific Ocean Tectonic Domain. The Fanchang Basin is the natural laboratory to study internal relations and timespace relations of the Mesozoic tectonismbasin formation-magmatism-mineralization in East China. The Fanchang Basin at the southern margin is located within the knot of the Middle and Lower Yangtze River, which has three tectonic orecontrolling characteristics：① The Tongling-Nanling Fault Zone is the firstorder orecontrolling structure. It is the oretransporting and orecontrolling structures of the polymetallic deposits in this area. ②The Yanshanian superimposed folds are the secondary-order orecontrolling structures which controls the transportation and emplacement of the hydrothermal oreforming solution. ③ The geologic bodies containing ores are third-order ore-controlling structures, some ideal spaces for ores transportation and accumulation. The Indosinian and Yanshanian tectonic movements provide favorable channels and emplacement spaces for the transfer of the Yaojialing polymetallic mineralizied fluids： ④Rocktransporting structures mainly consist of the Nanling Fault Zone. ⑤Oretransporting structures consist of the Tongling-Nanling Fault Zone, spactial belts among lenticular bodies, bedding planes of folds between orecontaining lenticular bodies, fault belts between beds and cracks paralleling to hinges of folds. ⑥ Oreaccumulating structures are up and lower boundary of ore-containing lenticular bodies, beds of folds between lenticular bodies, fault belts between beds and cracks oaralleling to hinges of folds.