GEOCHEMISTRY AND TECTONIC IMPLICATIONS OF KARAMAILI OPHIOLITE IN EAST JUNGGAR OF XINJIANG
GEOCHEMISTRY AND TECTONIC IMPLICATIONS OF KARAMAILI OPHIOLITE IN EAST JUNGGAR OF XINJIANG
复制标题
DOI：
--
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Lu Rong-hui
中科院分区：
文献类型：
--
作者：
Lu Rong-hui
新疆东准噶尔卡拉麦里蛇绿岩由变质橄榄岩、辉长岩、闪长岩和基性熔岩组成，其中辉长岩的LA-ICP-MS锆石U-Pb年龄为329.9Ma ± 1.6Ma，卡拉麦里蛇绿岩残片中的基性熔岩和辉长岩在球粒陨石中呈扁平状，结合卡拉麦里地区野外地质特征，结合岩石地球化学和高精度年代学研究，认为卡拉麦里洋盆开启于泥盆纪早期，闭合于石炭纪晚期的谢尔普霍夫期。
The Karamaili ophiolite complex in East Junggar of Xinjiang province was composed of metamorphic peridotite,gabbro,diabase and basic lava.LA-ICP-MS zircon U-Pb dating of gabbro from the Karamaili ophiolite revealed an isotopic age of 329.9 Ma±1.6 Ma,indicated that the Karamaili ophiolite occurred in the Visean of Early Carboniferous.The basic lava and gabbro in Karamaili ophiolite fragment showed flat patterns in chondrite-normalized REE diagram and primitive mantle-normalized trace elements diagram with low LILE abundance and no characteristics of IAT and OIB.These geochemical characteristics were similar to MORB and different from IAT and OIB,indicating that the ophiolite may be formed in middle ocean ridge.Combination of field geological feature of Karamaili region,with petrogeochemistry and high-precision geochronology,it was concluded that Karamaili ocean basin opened in early stage of Devonian and closed in the Serpukhovian during late Carboniferous.