楚雄盆地砂岩铜矿床同位素特征及矿床成因

楚雄盆地砂岩铜矿形成于白垩系高峰寺组凹地苴段、马头山组六苴段和大村段,以六苴、郝家河及大村铜矿床为代表。不论是硫同位素,还是氢氧同位素、铅同位素,六苴铜矿床和郝家河铜矿床均不相同。六苴铜矿硫化物中的硫以来自围岩为主,成矿溶液来自上部天水和建造水,成矿金属物质来自围岩,推测成岩成矿作用是主要矿化机制。而郝家河铜矿,成矿物质更多的是来自地下深处,与深部地下水循环作用有关,表明郝家河铜矿床以改造成矿为主。

ISOTOPIC CHARACTERISTICS AND GENESIS OF THE SANDSTONE-TYPE COPPER DEPOSITS IN THE CHUXIONG BASIN, YUNNAN PROVINCE

The sandstone-type Cu deposits in th e Chuxiong basin occur in the Cretaceous Gaofengsi Formation and Maotoushan Formation and these o re deposits are represented by the Luju copper deposit and Haojiahe copper deposit.There are difference between the sulfur,hydrogen,oxygen and lead isotope of the Luju copper deposit and Haojiahe copper d eposit.The sulfur of the Luju copper deposit came from the host,the mineralized solution from the rain a nd formation water,and the copper mi ght stem from the country rocks.It shows that minerogenesis may be main ly formed by diagenesis.In the Haoji ahe copper deposit,mineralized material came from deep-seated sour ce,and the minerogenesis is connected with the deep-water current.