CONVECTIONAL CURRENT THEORY
WHAT IS CONVECTIONAL CURRENT THEORY?
- In 1930s, Arthur Holmes discussed this theory with the possibility of convection currents in the mantle.
- He considered it as the soul of Seafloor Spreading Theory.
WHAT IS THE MECHANISM OF CONVECTIONAL CURRENT THEORY?
- The extreme heat is generated by radioactive chemicals in the mantle (100-2900 km down the earth's surface).
- The heat seeks a way to escape and causes convection currents in the mantle.
- Divergent convective currents pull crustal blocks away from each other.
- Convergent convective currents create subsidence in the crustal zones
- The movement of lithospheric plates is caused by the movement of the magma in the mantle.
- How much amount of heat needed for mechanism to occur?
- Convective currents may not be formed if heat is insufficient.
- This process may result in heat loss, which could cause currents to weaken.