Characteristics of ore-forming fluids of iron and copper ore-deposits in Lujiang-Zongyang volcanic basin

摘要

Lujiang-Zongyang volcanic basin is an important metallogenic concentration region in the middle part of the middle and lower reaches of Yangtze River metallogenic belt. It is located in the intersection between the Zhangbaling-Feidong structural zone and the middle and lower reaches of Yngtze River depressed belt those are all in the southeast of Dabie orogenic belt. Because of the Mesozoic intensive structure-magma activities, many ore deposits, such as Longqiao iron deposit, Luohe iron deposit, Shaxi copper deposit, were formed. A few researches on strata, magmatic rocks, ore deposits in this region have been done. But only few studies on ore-forming process, especially ore-forming fluid were reported, while some survey and analysis were done about in 1980's. According to the basic geological studies, combining with the studies of the ore-forming fluid inclusions of the main ore deposits, it is concluded that there are four stages of ore-forming activities of the iron and copper ore-deposits in Lujiang-Zongyang volcanic basin, and the characteristics of these ore-forming fluids are different obviously.