Seismolgists get handle on heat flow deep in Earth

Seismologists detected a lens-shaped structure (blue) within a large pile of chemically distinct material at the boundary between the liquid outer core and the solid mantle, half-way to the center of the Earth. The tubes rising from the edges of the pile represent plumes of hot mantle material rising toward the surface. The core-mantle boundary is the curved orange surface, and the small red ball is the solid inner core. (Image by Edward Garnero)