巨大地幔柱驱动非洲大陆分裂

研究人员通过三维热机械模型发现，深埋非洲下方的巨大地幔柱——非洲超级地幔柱产生的北向地幔流，可以解释东非裂谷系统中与裂谷平行的异常变形现象1。该超级地幔柱从西南非洲深处向东北方向延伸1，其地幔流方向与当地地震各向异性方向相一致1。

这项研究基于超过12年的GPS测量数据1，揭示了深层地幔流与浅层岩石圈浮力的耦合作用如何共同推动非洲大陆的逐步分裂1。研究成果已发表在《地球物理研究杂志》上1，由新墨西哥理工学院博士后研究员Tahiry Rajaonarison担任论文第一作者1。这一发现为理解东非裂谷系统——地球上最大的大陆裂谷系统的形成机制提供了新的认识1。

Researchers have identified a vast mantle plume deep below Africa that is driving the gradual separation of the continent, according to findings published in the Journal of Geophysical Research 1. Using three-dimensional thermomechanical modeling, scientists discovered that the African Superplume generates a northward-flowing mantle current that explains the anomalous deformation observed parallel to the rift zones within the East African Rift System 1. This deep-seated mantle flow works in conjunction with shallow lithospheric buoyancy forces to produce the continental extension occurring across the region 1.

The research team, led by postdoctoral researcher Tahiry Rajaonarison from New Mexico Institute of Mining and Technology, analyzed over 12 years of accumulated GPS measurement data to verify their findings 1. The East African Rift System represents the world's largest continental rift system 1. The team's analysis revealed that the northward mantle flow direction aligns with seismic anisotropy patterns detected at the surface, further corroborating the connection between deep mantle dynamics and the observed rifting patterns 1. This research provides a more nuanced understanding of how continental rifting processes operate by demonstrating the critical interplay between deep mantle convection and crustal deformation 1.