土屋-延东铜钼矿田与成矿有关问题的讨论

A Discussion on Problems Related to Mineralization of Tuwu-Yandong Cu-Mo Orefield in Hami, Xinjiang

为查明新疆土屋_延东铜矿的围岩地层时代、成矿时代和成矿环境等问题 ,文章通过野外调查、岩矿鉴定、古生物化石鉴定和同位素年代学等方面的研究 ,提出围岩地层为石炭系而不是泥盆系 ;锆石SHRIMP定年结果表明 334.6～ 32 0Ma为围岩火山岩的形成时代 ,另外还有两期岩浆活动 (4 34～ 4 2 6Ma和 2 6 0Ma) ;含矿直接围岩主要是斜长花岗斑岩而不是闪长玢岩 ;矿田隶属觉罗塔格构造_成矿带而不是哈尔里克带 ;矿田内斑岩类以及矿带中的石炭纪花岗岩类具埃达克岩特征 。

The Tuwu_Yandong Cu_Mo deposit is a super_large porphyry deposit discovered in recent years. Fossils indicate that the host rocks are of Carboniferous instead of Devonian. SHRIMP dating results of zircons from the host volcanic rocks give three groups of data, in which the ages from 334.6 Ma to 320 Ma indicate the rock_forming epoch of host rocks, while the ages from 434 Ma to 426 Ma and the age of 260 Ma show other two epochs of magmatism. The host rocks of mineralization are plagiogranitic porphyry rather than dioritic porphyry. The orefield is located in the Jueluotage tectonic_mineralization belt, not in the Haerlik belt. The adakite features of the porphyry rocks in the orefield and the Carboniferous granitoids in this region suggest good prospects in search for porphyry_type copper deposits in East Tianshan region.