Answer: Convection Currents
Step-by-step explanation:
Due to the different temperature occurring at the upper and lower layers of the mantle, it causes heat transfer to occur. One of such heat transfer is the Convection currents which causes warmer, less dense rock material in the core to rise through the mantle. Also, the cooler rocks in the higher mantle move slowly towards the core.The movement caused by these Convection current in the Earth are called plate tectonics which are responsible for earthquakes and volcanoes.