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安徽铜陵老鸦岭铜矿床是长江中下游地区的一个典型的层状矿床，以远离侵入岩体和赋存于二叠系钙质－硅质岩中为特征，其矿石矿物组合简单，近矿围岩蚀变较弱，为绢云母化、高岭石化、碳酸盐化和绿泥石化等，且分带性不明显。按照矿物形成的时间序列，矿床矿物可分为四个共生组合：（1）磁黄铁矿＋黄铁矿组合；（2）黄铜矿＋黄铁矿＋闪锌矿＋磁黄铁矿组合；（3）石英＋黄铜矿组合；（4）方解石＋黄铜矿组合。矿物包裹体以气液两相为主，气液比从早到晚逐渐减小直至成为单一的液相。均一法测温表明，组合1的均一温度为290～320℃，组合2为240～265℃，组合3为180～220℃，和组合4为110～116℃。矿物包裹体液相成分属于NaCl－H_2O体系，并含有F~－和，盐度小于10wt％。根据热力学计算，圈定了矿物共生组合的物理化学场，从组合1到4，成矿热液的fo_2、fs_2及∑S浓度依次降低，pH值变化不大，但还原性降低，氧化性增强。矿床硫同位素组成δ~34S_∑S为：组合1是＋0．5％。，组合2为1‰～3‰，组合3大于＋5‰和组合4大于＋6‰。这证实成矿热液中硫来源于岩浆，并随着时间的演化有地层硫的加入。氧和氢同位素研究说明参与成矿作用的热液除岩浆源之外，还有相当多的大气水或地下水的加入。矿石普通铅同位素为异常
The Laojialing copper deposit, Tongling, Anhui Province, is a typical stratiform deposit in the middle and lower reaches of the Yangtze River. It is characterized by being far away from intrusive rocks and occurring in Permian calc-siliceous rocks. Its ore mineral assemblage is simple, Wall rock alteration weaker, sericite, kaolinite, carbonate and chlorite, etc., and the zoning is not obvious. According to the time series of mineral formation, the mineral deposits can be divided into four symbiotic combinations: (1) pyrrhotite + pyrite assemblage; (2) chalcopyrite + pyrite + sphalerite + pyrrhotite assemblage ; (3) quartz + chalcopyrite assemblage; (4) calcite + chalcopyrite assemblage. The mineral inclusions are dominated by gas-liquid two phases, and the gas-liquid ratio gradually decreases from morning to night until it becomes a single liquid phase. The homogenization temperature measurements showed that the homogenization temperature for combination 1 was 290-320 ° C, combination 2 was 240-265 ° C, combination 3 was 180-220 ° C, and combination 4 was 110-116 ° C. The liquid inclusions of mineral inclusions belong to NaCl-H_2O system and contain F ~ - and the salinity is less than 10wt%. According to the thermodynamic calculation, the physicochemical field of the symbiotic assemblage of minerals was delineated. From combinations 1 to 4, the concentrations of fo_2, fs_2 and ΣS in the hydrothermal fluids decreased in turn, while the pH did not change much, but the reducibility decreased and the oxidation increased. Sulfur isotope composition of δ ~ 34S_ΣS is: combination 1 is + 0.5%. , Combination 2 is 1 ‰ ~ 3 ‰, combination 3 is greater than + 5 ‰ and combination 4 is greater than + 6 ‰. This confirms that the sulfur in ore-forming hydrothermal fluids is derived from magma, and the formation of formation sulfur is added over time. Oxygen and hydrogen isotope studies indicate that in addition to the magmatic source of mineralization involved in mineralization, there is a considerable amount of atmospheric water or groundwater added. Ordinary lead isotope of ore is abnormal