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峨眉山大火成岩省和西伯利亚大火成岩省是发生于二叠 -三叠纪之交的重要岩浆事件。它们在主要元素、微量元素和Sr、Nd、Pb同位素特征上具有相似姓 ,但是峨眉山大火成岩省的不相容元素比值和同位素比值的变化范围相对要小一些。相对而言 ,峨眉山玄武岩具有高的Fe8和Sm/Yb值 ,暗示了其熔融深度较西伯利亚大火成岩省深 ,而熔融程度较低 ,两者的源区均为石榴石二辉橄榄岩。根据Nd同位素特征估算峨眉山和西伯利亚地幔柱的 Nd≈ 2 ,接近于原始地幔特征。综合其他地球化学特征 ,认为两个大火成岩省可能起源于同一个来自于核 -幔边界的超级地幔柱
The Emeishan Igneous Province and the Siberia Igneous Province are important magmatic events that took place at the turn of the Permian-Triassic period. They have similar surnames in major elements, trace elements and Sr, Nd and Pb isotopic characteristics, but the range of incompatible elements and isotopic ratios in the Emeishan Igneous Province is relatively small. Relatively speaking, the Emeishan basalts have high Fe8 and Sm / Yb values, indicating that their melting depth is deeper than that of the Great Siberian igneous rocks and their melting degrees are relatively low. Both of the source regions are garnet lherzolites. The Nd ≈ 2 estimated from the Nd isotopes of Emei and Siberia mantle plumes is close to the original mantle characteristics. Combined with other geochemical characteristics, it is believed that the two large igneous provinces may originate from the same super-mantle plume from the core-mantle boundary