In geology, the term exhumation refers to the process by which a parcel of rock approaches Earth's surface. It differs from the related ideas of rock uplift and surface uplift in that it is explicitly measured relative to the surface of the Earth, rather than with reference to some absolute reference frame, such as the Earth's geoid.Exhumation is almost a synonym for denudation, except some authors have considered the former to be in the frame of reference of the uplifted rock, and the latter to be in the frame of reference of the surface towards which rocks are advected.
Exhumation of rocks occurs either by erosion or by extensional tectonics. Because the movement of rocks from depth towards the surface cools them, thermochronometric methods like fission track or radiometric dating strictly measure exhumation, not rock uplift or erosion rates.
Outside tectonics, geological exhumation can also describe the return to Earth's surface of something previously buried in sediments, for example a landform.