How can convection be observed in geological processes?

Convection can be observed in geological processes primarily through mantle convection leading to plate tectonics. This process involves the movement of the Earth's mantle, where hot material rises toward the surface, cools, and subsequently sinks back down. As the hot molten rock rises, it pushes tectonic plates apart, while cooler material descends, creating a cycle known as convection currents. This is a crucial mechanism that explains the movement of tectonic plates on the Earth's surface, contributing to the formation of continents, ocean basins, and the occurrence of earthquakes and volcanic activity.

The other options do not directly represent convection processes in geology. Atmospheric heat exchange relates to convection in the atmosphere but is not a geological process. Erosion of rocks mainly involves mechanical and chemical breakdown rather than movement due to convection. Similarly, while the melting of glaciers is related to heat transfer, it does not exemplify convection as it does not involve the movement of fluids in a cycle typical of convective processes.