The moho is the boundary at what two layers of the earth?
The Moho discontinuity, or "Moho", is the boundary between the Earth's crust and the mantle. Here, rocks of the crust differ from the rocks of the upper layer of mantle.
Moho was discovered in 1909 by Andrija Mohorovicic This geological discontinuity is used to explain a surface at which seismic waves increase velocity. Moho is closer, at about 10 kilometers, to the ocean base. It is farther, at about 30 kilometers, beneath the continents.