Final answer:
The movement of large plates on Earth is due to plate tectonics, driven by convection currents in the Earth's asthenosphere.
Step-by-step explanation:
The movement of large plates on Earth is due to a process called plate tectonics. The Earth's lithosphere, which is made up of several large plates, is constantly moving. This movement is caused by convection currents in the underlying asthenosphere. These convection currents are driven by the heat from the Earth's interior, causing the plates to move apart, collide, or slide past each other. For example, the Pacific Plate is moving northwestward, causing it to collide with the North American Plate along the western coast of North America.
Learn more about Plate tectonics