What is a mid-ocean ridge?
A mid ocean ridge is a divergent boundary where hot magma from the mantle comes to the surface under the ocean creating mountains and undersea volcanos.
In most of the world's oceans, there is a divergent boundary. The divergent boundary is a place where two plates are moving in opposite directions. The weak place in the crust where the plates are separating allows hot magma from the mantle to come to the surface. The hot magma coming to the surface creates the mid ocean ridges.
The theory of plate tectonics proposes that these divergent boundaries are created by convection currents in the mantle. The divergent boundary is thought to be a point in the convection current where the hottest liquid ( semi liquid magma) is rising to the surface.
A mid ocean ridge is a divergent boundary in the tectonic plates where hot magma is coming to the surface, due to convection currents, creating mountains and volcanos.