Tectonic uplift

While isostatic response is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of crustal thickening (such as mountain building events), changes in the density distribution of the crust and underlying mantle, and flexural support due to the bending of rigid lithosphere.

Although the raised surfaces of mountain ranges mainly result from crustal thickening, there are other forces at play that are responsible for the tectonic activity.

The dynamics of mountain ranges are governed by differences in the gravitational energy of entire columns of the lithosphere (see isostasy).

For example, the lithosphere on the oceanward side of an oceanic trench at a subduction zone will curve upwards due to the elastic properties of the Earth's crust.

[2] The collision of the Indian and Eurasian plates produced the Himalayas and is also responsible for crustal thickening north into Siberia.

The Ozark Plateau is a broad uplifted area which resulted from the Permian Ouachita Orogeny to the south in the states of Arkansas, Oklahoma, and Texas.

The Colorado Plateau which includes the Grand Canyon is the result of broad tectonic uplift followed by river erosion.

[4] When mountains rise slowly, either due to orogenic uplift or other processes (e.g., rebound after glaciation), an unusual feature known as a water gap may occur.

Therefore, in most convergent boundaries, isostatic uplift plays a relatively small role, and high peak formation can be more attributed to tectonic processes.

[6] Direct measures of the elevation change of the land surface can only be used to estimate erosion or bedrock uplift rates when other controls (such as changes in mean surface elevation, volume of eroded material, timescales and lags of isostatic response, variations in crustal density) are known.

Exhumation rates can be inferred from fission tracks and from radiometric ages as long as a thermal profile can be estimated.