GEOLOGY

Detailed explanation-1: -Mantle convection describes the movement of the mantle as it transfers heat from the white-hot core to the brittle lithosphere. The mantle is heated from below, cooled from above, and its overall temperature decreases over long periods of time. All these elements contribute to mantle convection.

Detailed explanation-2: -Mantle convection occurs because relatively hot rocks are less dense and rise in a gravitational field while relatively cold rocks are more dense and sink. The rise of hot rocks advects heat upward while the fall of cold rocks advects cold downward; this counterflow is equivalent to an upward heat flux.

Detailed explanation-3: -Heat from the Earth’s core is transferred outward along the mantle, causing the hot material at the bottom of the mantle to rise and colder material from the top to sink. This creates a cycle of rising hot material and sinking cold material, resulting in the formation of convection currents.

Detailed explanation-4: -Convection currents are the result of differential heating. Lighter (less dense), warm material rises while heavier (more dense) cool material sinks. It is this movement that creates circulation patterns known as convection currents in the atmosphere, in water, and in the mantle of Earth.