Olivine, a common mineral in Earth’s upper mantle, typically transforms into ... scientists have both solved the mystery of impossible-depth earthquakes and established clear limits to how ...

The transition between the upper and lower mantle occurs at about 660 km below Earth's surface. At this depth certain minerals undergo a phase transition. Deng and colleagues believe that this ...

(b) Schematic diagram of the upper mantle structure beneath the Tonga-Lau ... a high-resolution 3D velocity model extending to 300 km depth. Rigorous validation through checkerboard and restoring ...

The potential compositional boundary was typically put at 660 km depth, corresponding to the major seismic discontinuity that marks the boundary between the upper mantle and lower mantle.