he boundary between the Earth's crust and the underlying upper mantle is now recognised by a significant increase in the velocity of seismic P-waves at depths between 15 and 50 km depth

Biology May 24, 2021

he boundary between the Earth's crust and the underlying upper mantle is now recognised by a significant increase in the velocity of seismic P-waves at depths between 15 and 50 km depth. This velocity increase indicates a major change in the composition of the rocks at that boundary. The boundary is now called the Mohorovicic Discontinuity