GEOLOGY

Detailed explanation-1: -Magma is the molten rock below the crust, in the mantle. Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth’s crust.

Detailed explanation-2: -Convection currents are heat-driven cycles that occur in the air, ocean, and mantle. They are caused by a difference in temperature, often due to a differing proximity to a heat source. The difference in temperature relates directly to the density of the material, causing this effect.

Detailed explanation-3: -Convection currents rise and spread below divergent plate boundaries and converge and descend along convergent. The convection currents are sought to be produced by three sources: first the cooling of the Earth’s core, second the radioactivity within the mantle and crust and third through the cooling of the mantle.

Detailed explanation-4: -The driving force for natural convection is gravity. For example if there is a layer of cold dense air on top of hotter less dense air, gravity pulls more strongly on the denser layer on top, so it falls while the hotter less dense air rises to take its place. This creates circulating flow: convection.