Final answer:
The large-scale movement of lithospheric plates is driven by convection currents in the mantle. Convection currents are circular patterns of motion caused by the heating and cooling of material.
These currents push and drag the plates on the Earth's surface.
Step-by-step explanation:
The large-scale movement of lithospheric plates is driven by convection currents in the mantle.
Convection currents are circular patterns of motion caused by the heating and cooling of material. In the mantle, hot material near the core rises, while cooler material near the surface sinks.
This creates a continuous cycle of upward and downward movement that pushes and drags the lithospheric plates on the Earth's surface.
For example, at divergent plate boundaries like the Mid-Atlantic Ridge, convection currents create tension that pulls the plates apart, allowing magma to well up and form new crust. At convergent plate boundaries like the Pacific Ring of Fire, convection currents cause plates to collide, leading to processes like subduction and the formation of volcanic arcs.