岩石矿物学杂志2017，Vol.36Issue(2)：131-147,17.
北山造山带白云山蛇绿混杂岩的地球化学特征、时代及地质意义
Geochemical characteristics and U-Pb age of Baiyunshan ophiolite mélange in the Beishan orogenic belt and their geological implications
摘要
Abstract
The Baiyunshan ophiolite mélange is a part of the Hongliuhe-Niujuanzi-Xichangjing ophiolite belt in the Beishan orogenic belt and has a complete sequence composed of serpentinized lherzolite,serpentinite,gabbro (cumulate gabbro,massive gabbro),mafic pillow lavas (metabasalt) and bathyal-abyssal or pelagitehemipelagite facies sediments (silicalite,slate),dolomite and some other kinds of rocks.Zircon LA-ICP-MS Upb dating results indicate that the gabbro has the age of 496.4 ± 2.2 Ma,indicating that this ophiolite was formed in Late Cambrian.Geochemical characteristics of pillow basalts in the ophiolite mélange show dual nature of ocean floor alkaline basalt (OIB) and middle ocean ridge basalt (MORB);in addition,pillow basalts appear alternately with silicalites.All the evidence suggests that they formed in the deepwater ocean basin.Regional geological analyses indicate that the Baiyunshan ophiolite mèlange represents a relic of early Paleozoic middle ocean ridge.关键词
蛇绿混杂岩/岩石地球化学特征/时代/白云山/北山地区Key words
ophiolite mélange/geochemical characteristics/age/Baiyunshan/Beishan area分类
天文与地球科学引用本文复制引用
孙立新,张家辉,任邦方,牛文超,任云伟,张阔..北山造山带白云山蛇绿混杂岩的地球化学特征、时代及地质意义[J].岩石矿物学杂志,2017,36(2):131-147,17.基金项目
中国地质调查局地质调查项目(12120114064601)Project of China Geological Survey (12120114064601) （12120114064601）
