青海直河蛇绿岩地质特征及找矿前景

Geological characteristics and prospecting analysis of ophiolites around Zhihe Belts in Qinghai

经1∶5万区域矿产地质调查所发现的直河蛇绿岩带,位于北祁连褶皱带冷龙岭复式背斜北翼中带,不但具大洋拉斑玄武岩特征,还具有岛弧特征,为弧后盆地拉张环境产物;蛇绿岩中铜、锌、镍、钴含量较高,在该带中已发现直河铜矿、干树湾铜矿等多处铜矿点,分布较为密集,均赋存于蛇绿岩带海相中基性火山岩中,典型矿化特征可与塞浦路斯型铜矿床相一致。直河地区蛇绿岩带的发现,对该区今后寻找与蛇绿岩有关的塞浦路斯型铜矿床具有重要的指导意义。

ZhiHe ophiolite belt, discovered during the 1： 50 thousand scale regional geological survey of mineral resources, is located in middle belt of the north wing of Lenglongling duplex anticline in the North Qilian fold belt. Zhihe belt not only has characteristics of oceanic tholeiite, but also have the island arc characteristics and is the product formed in the back arc basin extensional environment. The ophiolite belt which contained higher content copper, zinc, nickel and cobalt had found various copper oeeurenee such as Zhihe copper occurrence and Ganshuwan copper occurrence, with the distribution of more intensive. All of those copper occurrences occur in the marine basic volcanic rocks in the ophiolite belt, and have the typical characteristics of the Cyprus type copper deposits. Discovery of ZhiHe ophiolite belt have an important guiding significance to look for the Cyprus type copper deposits related to the ophiolite in this area.