某些大洋玄武岩具有异常的同位素特征,不同于同一空间的地幔羽但却是古老的大陆岩石圈地幔(如Hawkesworth等,1986)或古老的下陆壳(Kamenetsky等,2001)的典型特征。这些异常组分被认为是大陆开裂期间分离出来并被运移到大洋地幔浅处的岩石圈物质。羽状物的热侵蚀和裂谷作用导致 Some oceanic basalts have anomalous isotopic characteristics that differ from the mantle plumes in the same space but are typically characteristic of ancient continental lithospheric mantle (eg, Hawkesworth et al., 1986) or the ancient continental crust (Kamenetsky et al., 2001). These anomalous components are believed to be lithospheric materials that have been separated during the cracking of the mainland and migrated to the shallow mantle of the ocean. The thermal erosions and rifting of plumes result