西北地质2017，Vol.50Issue(1)：35-49,15.
柴达木西北缘古生代镁铁-超镁铁质岩体Cu-Ni成矿条件与找矿潜力分析
Analysis on the Prospecting Potentiality and Cu-Ni Metallogenic Conditions of the Paleozoic Mafic-ultramafic in the Northwestern Margin of Qaidam Basin
摘要
Abstract
The Paleozoic mafic-ultramafic rocks, located in the northwestern margin of the Qaidam Basin, were emplaced in the Paleoproterozoic Jinshuikou Group, which spread in the north-eastern direction with zonal distribution.From west to east, these rocks can be divided into Niubiziliang intrusion, Datonggounanshan intrusion, Qingxinjieshan intrusion, and Qaidam Gate intrusion.These mafic-ultramafic rock bodies are mainly occurred as vein and lenticular, with many rock types, such as, olivine pyroxenolite, websterite and gabbro.From the core to its edge,this complex is composed of peridotite, pyroxenite and gabbro.The mineralization of nickel and copper is closely related to peridotite and pyroxenite.Zircon U-Pb geochronology and geological background research show that Datonggounanshan intrusion and Qaidam Gate inrusionare probably related to the subduction of oceanic crust in the Early Paleozoic (458.3 Ma and 453 Ma), while the Niubiziliang intrusion was formed the Late Paleozoic period (402 Ma) under the setting of from the late stage of the collisional orogenic to the post-orogenic extension.The comprehensive studies of the field observations, petrology and geochemistry show that the crystallization differentiation and crustal contamination were occurred in the magma chamber, implying that these intrusions have good potential of forming the copper and nickel ore.The MgO contents of the intrusions vary from 8.39% to 31.15%, their M/F ratios range from 2.0 to 4.6, with an average of 3.8, indicating that these intrusions belong to the ferruginous ultrabasic rocks.The average value of K2O/Na2O is 2.4.The above data shows that the ultramafic rocks have good condition for the mineralization of nickel and copper.关键词
找矿潜力/成矿条件/铜镍矿/古生代镁铁-超镁铁质岩体/柴达木盆地西北缘Key words
ore-prospecting potential/metallogenic condition/copper-nickel deposit/Paleozoic mafic-ultramafic intrusions/northwestern margin of Qaidam Basin分类
天文与地球科学引用本文复制引用
钱兵,张照伟,刘会文,邵继,王亚磊..柴达木西北缘古生代镁铁-超镁铁质岩体Cu-Ni成矿条件与找矿潜力分析[J].西北地质,2017,50(1):35-49,15.基金项目
国土资源部公益性行业科研专项"拉陵灶火镍成矿赋矿机理及勘查技术研究示范"(201511020),国家自然科学基金青年基金"西昆仑赞坎条带状铁矿中高品位磁铁矿形成机制研究"(41603050)和"新疆东天山白鑫滩铜镍硫化物矿床岩石成因及成矿机制研究"(41602094),中国地质调查局"东昆仑铜镍多金属资源基地调查"二级项目(DD20160013) （201511020）
