东秦岭发现～1.9Ga钼矿床——河南龙门店钼矿床Re-Os定年

Discovery of a～1.9Ga Mo deposit in the eastern Qinling orogen:Molybdenite Re-Os ages of the Longmendian Mo deposit in Henan Province

河南龙门店钼矿床位于华北陆块南缘熊耳山地区,其赋矿围岩为新太古代-古元古代太华群片麻岩。6件辉钼矿样品的Re-Os模式年龄最小值为1868±6Ma,最大值为2044±14Ma,等时线年龄为1875Ma,表明该矿床形成于早元古代,是目前我国已知最老的钼矿床。

The Longmendian Mo deposit,located in the Xiong ershan area of Henan Province,is hosted in Archean-Paleozoic gneisses of the Taihua Group in the southern margin of the North China craton.Re-Os model ages of five molybdenite samples range from 1868±6Ma to 2044±14Ma and give an isochron age of 1875Ma.These ages suggest that the Longmendian Mo deposit was formed during Palaeoproterozoic,and is the oldest Mo deposit found in China.