Here's a breakdown:
* Crust: The outermost solid layer of Earth, composed of relatively light, less dense rock.
* Upper Mantle: The layer beneath the crust, made of denser rock.
* Moho: The boundary between these two layers, identified by a sharp increase in seismic wave velocity.
Why the change in velocity?
The Moho marks a transition from the relatively lighter, less dense rocks of the crust to the denser, heavier rocks of the upper mantle. This difference in density causes seismic waves to travel faster through the mantle.
Importance of the Moho:
The Moho is a significant geological boundary because it helps scientists understand the structure and composition of Earth's interior. It also plays a role in plate tectonics, as the Moho is often a zone of weakness where the crust can break and move.
