福建省永定大排铁铅锌多金属矿矿床特征及成矿时代

Geological characteristics and metallogenic epochs of the Dapai Fe-Pb-Zn polymetallic deposit in Yongding County, Fujian Province

摘要: 福建永定大排铁铅锌多金属矿床是闽西南地区近年来发现的大型多金属矿床。对矿区内蚀变花岗岩的锆石SHRIMP U-Pb定年和辉钼矿Re-Os同位素测年结果显示其分别形成于(127.0±1.8) Ma和(133.5±4.1) Ma,这一年龄与区内马坑铁矿及潘田铁矿的成岩成矿年龄相一致,指示区域上该期铁铅锌多金属矿与区内花岗质岩浆作用有密切的时间和成因联系,大排铁铅锌多金属的主成矿期可能为燕山期。结合已有的区域地质资料及研究成果,认为福建永定大排铁铅锌多金属矿床可能为层控矽卡岩型-斑岩型复合型矿床。

Abstract: The Dapai Fe-Pb-Zn polymetallic ore deposit in Yongding County of southwestern Fujian Province is a large-sized polymetallic deposit discovered in recent years. Zircon SHRIMP U-Pb dating of Dapai altered granodiorite is (127±1.8) Ma, equal to the Re-Os isotopic age (133.5±4.1) Ma of the granodiorite porphyry. Both ages are consistent with the age of Makeng and Pantian iron ore deposit in the same area, indicating genetic relation between the granitic magmatism and the Fe-Pb-Zn metallogenesis in the area, with the main metallogenic epoch being Yanshanian. Based on the previous research results and data obtained by the authors, it is inferred that the Dapai Fe-Pb-Zn polymetallic ore deposit belongs to stratabound skarn-porphyry type composite deposit.