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tectonic uplift
Tectonic uplift is the portion of the total geologic uplift of the mean Earth surface that is not attributable to an isostatic response to unloading. Whereas 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.
It is also good to take into consideration the effects of denudation (processes that wear away the earth's surface). Within the scope of this topic, uplift relates to denudation in that denudation brings buried rocks closer to the surface. This process can redistribute large loads from an elevated region to a topographically lower area as well – thus promoting isostatic response in the region of denudation (which can cause local bedrock uplift). The timing, magnitude, and rate of denudation can be estimated using pressure-temperature studies.
==Crustal thickening==
Crustal thickening has an upward component of motion and often occurs when continental crust is thrust onto continental crust. Basically nappes (thrust sheets) from each plate collide and begin to stack one on top of the other; evidence of this process can be seen in preserved ophiolitic nappes (preserved in the Himalaya), and in rocks with an inverted metamorphic gradient. The preserved inverted metamorphic gradient indicates that nappes were actually stacked on top of each other so quickly, that hot rocks did not have time to equilibrate before being thrust on top of cool rocks. The process of nappe stacking can only continue for so long, as gravity will eventually disallow further vertical growth (there is an upper limit to vertical mountain growth).
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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