In geology, denudation is the long-term sum of processes that cause the wearing away of the Earth’s surface by moving water, ice, wind and waves, leading to a reduction in elevation and relief of landforms and landscapes. Endogenous processes such as volcanoes, earthquakes, and plate tectonics uplift and expose continental crust to the exogenous processes of weathering, erosion, and mass wasting.
Denudation incorporates the mechanical, biological and chemical processes of erosion, weathering and mass wasting. Denudation can involve the removal of both solid particles and dissolved material. These include sub-processes of cryofracture, insolation weathering, slaking, salt weathering, bioturbation and anthropogenic impacts.
Factors affecting denudation include:´
Modern denudation estimates are usually based on stream load measurements taken at gauging stations. Suspended load, bed load, and dissolved load are included in measurements. The weight of the load is converted to volumetric units and the load volume is divided by the area of the watershed above the gaging station. The result is an estimate of the wearing down of the Earth's surface in inches or centimeters per 1000 years. In most cases no adjustments are made for human impact, which causes the measurements to be inflated.
Denudation rates are usually much lower than the rates of uplift. The only areas at which there could be equal rates of denudation and uplift are active plate margins with an extended period of continuous deformation.