苏鲁造山带深部岩石圈的属性：来自麻粒岩和橄榄岩捕虏体的制约  

Tectonic Affinity of the Sub-Continental Lithosphere of the Sulu Orogenic Belts:Constraints from Granulite and Peridotites Xenoliths

作　　者：英基丰[1] 张宏福[1] 周新华[1] 汤艳杰[1] 

机构地区：[1]中国科学院地质与地球物理研究所,岩石圈演化国家重点实验室,北京100029

出　　处：《矿物岩石地球化学通报》2013年第3期328-334,共7页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-EW-QN106);国家自然科学基金资助项目(91214203)

摘　　要：位于苏鲁造山带内的山东莒南晚白垩纪玄武质脉岩中含有大量地幔橄榄岩和下地壳麻粒岩捕虏体,这些捕虏体为苏鲁造山带陆下岩石圈的属性提供了重要制约。系统的年代学、矿物学、主微量元素和同位素研究表明莒南麻粒岩捕虏体是华北古老下地壳的样品,即苏鲁造山带的深部岩石圈具有华北属性。莒南橄榄岩捕虏体可以分为两类,占绝大多数的为低Mg#橄榄岩,少量高Mg#橄榄岩,橄榄岩的矿物成分以及单斜辉石微量元素组成特征表明,低Mg#橄榄岩代表了新增生的岩石圈地幔,而高Mg#橄榄岩反映的是受到熔体改造的古老岩石圈地幔的残留。苏鲁地区陆下岩石圈古老难熔的地幔至少在晚白垩纪时就已经被年轻饱满的新增生的地幔所代替。Granulite and peridotite xenoliths, trapped in a Cretaceous mafic dike in Junan, Shandong province, placed significant constraints on the tectonic affinity and evolutionary process of the sub-continental lithosphere be- neath the Sulu orogenic belts. Acquired results reveal that the deep lithosphere of the Sulu orogenic belts show an affinity with the North China craton rather than with the Yangtze craton. The lithospheric mantle is dominantly composed of newly accreted fertile peridotite with subordinate the remanent aged and refractory peridotite, implying that the momentous transformation of the lithospheric mantle beneath the Sulu orogen accomplished at least before the late Cretaceous.

关 键 词：苏鲁造山带 麻粒岩 橄榄岩 岩石圈演化 

分 类 号：P588.125[天文地球—岩石学]