This video shows a numerical simulation of Earth’s deep mantle. The top panel is temperature and the bottom panel is composition which includes three components: the more-primitive reservoir at the lowermost mantle (cyan), the subducted oceanic crust (yellow) and the depleted background mantle (black). Notice that as the oceanic crust is subducted to the lowermost mantle, some part of it is directly carried up to the surface by plumes which a large fraction of it episodically enters the more-primitive reservoir. As a result, plumes forming on top of the more-primitive reservoir could simultaneously entrain a combination of compositional components to the surface, including (a) relatively young oceanic crust, (b) ancient more-primitive material stirred with older oceanic crust, and (c) background, depleted mantle.
Credit: Mingming Li / Allen McNamara / Arizona State University
[ Read the Article: New Model Of Earth’s Dynamic Interior Developed ]