钦杭成矿带南段阳春盆地中侏罗世钨铅锌矿床的厘定及意义

钦杭成矿带是华南地区一条著名的中生代斑岩-矽卡岩铜铅锌多金属成矿带,其南段阳春盆地内以集中发育白垩纪钨锡多金属矿床为特征,侏罗纪成矿仅有个别铜铁钼矿床报道.因此,区内有关侏罗纪成矿特征、矿化元素组合、成岩成矿物质等问题尚不明晰.本文对阳春盆地内黑石岗矽卡岩型铅锌矿床和留洞石英脉型钨钼矿床进行了成岩成矿年代学研究.结果显...

Discovery and significance of Middle Jurassic W-Pb-Zn deposits in the Yangchun basin, southern Qin-Hang metallogenic belt

The Qin-Hang metallogenic belt is famous for amount of Mesozoic porphyry-skarn Cu-Pb-Zn polymetallic deposits in South China.The Yangchun basin is located in its southern part and is characterized by abundant Cretaceous W-Sn polymetallic ore deposits with few Jurassic Cu-Fe-Mo deposit.The Jurassic deposits in terms of metallogenic and metal associations in Yangchun basin are unclear.Here we present geochronologic data for Heishigang Pb-Zn-Cu deposit and Liudong W-Mo deposit in Yangchun basin.The Heishigang is a skarn deposit related to granodiorite and its orebody occur as laminated and lenticular in the contact between the granodiorite with the Carboniferous carbonate.Liudong ore-bearing quartz veins develop in the Cambrian metamorphic rock.Zircon UPb dating and molybdenite Re-Os geochronology indicate that the emplacement of the Heishigang granodiorite and the associated Pb-ZnCu mineralization occurred at 164.9±0.7 Ma,consistent with the Liudong W-Mo mineralization at 164.6±4.0 Ma.The results demonstrated that the Jurassic mineralization in Yangchun basin includes not only the Cu-Fe-Mo ores,but also W-Sn-Pb-Zn-Cu deposits.The rhenium contents of Liudong molybdenite samples are in the range of 514.0×10^-9~2370×10^-9,and the Heishigang rocks show negative zirconεHf(t)values(-5.2~-2.9),suggesting the W-Mo and magmas mainly generated through the old crustal components and a little mantle material inputted.This result highlights the potential for discovering the Jurassic ores in Yangchun basin,and also provides important information for further discussion on the geodynamic settings of Qin-Hang metallogenic belt.