Compositional heterogeneity of the asthenosphere: Advancement and implications

摘要: Asthenosphere is the mechanically weak and ductile region of Earth's upper mantle, which lies beneath the lithosphere and extends as deep as the mantle transition zone. Its global convection is responsible for driving tectonic movement of the plates. The asthenosphere is an important source of magmatic rocks on the Earth and has been regarded as essential reference reservoir applied to discussion on significant geological issues, such as Earth's formation and evolution, crust-mantle interaction, and crustal growth. Previous studies on oceanic basalts have proposed that the asthenosphere is relatively homogeneous in composition. Nevertheless, compositions of abyssal peridotites have shown that the asthenosphere is strongly heterogeneous. Numerous studies have shown that ancient mantle domains are ubiquitous within the asthenosphere, which could be originated from the recycled oceanic mantle and …