The Great Basin was primarily shaped by tectonic forces, particularly plate tectonics and faulting, which created its basin-and-range topography.

The Great Basin's unique landscape is the result of millions of years of tectonic activity, particularly the stretching and faulting of the Earth's crust. This caused the region to sink in some areas, forming large basins, while surrounding mountain ranges were uplifted. The faulting process creates the characteristic "basin-and-range" topography, with alternating valleys and mountains. Although glacial activity, rivers, and wind erosion have played a role in shaping the landscape, the primary factor remains plate tectonics and faulting that have redefined the region's geological structure over time.