What geological process leads to the formation of a rift valley?

The formation of a rift valley is primarily associated with divergent tectonic activity. This process occurs where tectonic plates move away from each other, allowing the lithosphere to stretch and thin. As the plates separate, the central part of the region subsides, creating a large, elongated depression known as a rift valley.

During this tectonic activity, magma from the mantle may rise to fill the gap created by the separating plates, which can lead to volcanic activity along the rift. The rift valley is typically characterized by steep valley walls and significant geological features such as faults and earthquakes due to the tectonic stress in the area.

In contrast, convergent tectonic activity, where plates collide, typically leads to the formation of mountain ranges or subduction zones, while transform tectonic activity involves plates sliding past one another and does not result in the creation of rift valleys. Erosional activity, while it can shape landforms, is not responsible for the formation of rift valleys, which are a direct result of tectonic processes. Thus, divergent tectonic activity accurately explains the geological processes that lead to the formation of a rift valley.