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{{Short description|Geologic uplift of Earth's surface that is attributed to plate tectonics}}
[[File:Raised beach western Crete.jpg|thumb|[[Raised beach]] indicating 9 m of uplift during the [[365 Crete earthquake]], other shorelines identified at this site are at 14 m, 17m, 34m, 55m & 75m elevation, consistent with a long-term uplift rate of 2.5–2.7 mm per year over the last 45,000 years]]
'''Tectonic uplift''' is the [[orogeny|geologic uplift]] of [[Earth#Surface|Earth's surface]] that is attributed to [[plate tectonics]]. While [[Isostasy|isostatic]] response is important, an increase in the mean elevation of a region can only occur in response to tectonic processes of [[Thrust tectonics|crustal thickening]] (such as [[Mountain formation|mountain building]] events), changes in the density distribution of the crust and underlying [[Mantle (geology)|mantle]], and flexural support due to the bending of rigid [[lithosphere]].
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{{Main|Orogeny}}
Orogenic uplift is the result of tectonic-plate collisions and results in mountain ranges or a more modest uplift over a large region. Perhaps the most extreme form of orogenic uplift is a continental-continental crustal collision. In this process, two continents are sutured together, and large mountain ranges are produced. The collision of the [[Indian
The [[Ozarks|Ozark Plateau]] is a broad uplifted area which resulted from the [[Permian]] [[Ouachita Mountains|Ouachita Orogeny]] to the south in the states of [[Arkansas]], [[Oklahoma]], and [[Texas]]. Another related uplift is the [[Llano Uplift]] in Texas, a geographical ___location named after its uplift features. The [[Colorado Plateau]] which includes the [[Grand Canyon]] is the result of broad tectonic uplift followed by river [[Erosion and tectonics|erosion]].<ref>Karlstrom, K.E., et al., 2012, ''Mantle-driven dynamic uplift of the Rocky Mountains and Colorado Plateau and its surface response: Toward a unified hypothesis,'' Lithosphere, v. 4, p. 3–22 [http://lithosphere.gsapubs.org/content/4/1/3.abstract abstract]</ref>
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==Uplift vs. exhumation==
The word "uplift" refers to displacement contrary to the direction of the gravity vector, and displacement is only defined when the object being displaced and the frame of reference is specified. Molnar and England<ref name=E&M/> identify three kinds of displacement to which the term
# Displacement of the Earth's surface with respect to the [[geoid]]. This is what we refer to as "surface uplift"; and surface uplift can be defined by averaging elevation and changes in elevation over surface areas of a specified size.
# The "uplift of rocks" refers to the displacement of rocks with respect to the geoid.
# The displacement of rocks with respect to the surface is called [[Exhumation (geology)|exhumation]].
This simple equation relates the three kinds of displacement:
::''Surface uplift = uplift of rock
The term geoid is used above to mean ''[[Sea level|mean sea level]]'' and makes a good frame of reference. A given displacement within this frame of reference allows one to quantify the amount of work being done against gravity.
Measuring uplift and exhumation can be tricky. Measuring the uplift of a point requires measuring its elevation change – usually geoscientists are not trying to determine the uplift of a singular point but rather the uplift over a specified area. Accordingly, the change in elevation of all points on the surface of that area must be measured, and the rate of erosion must be zero or minimal. Also, sequences of rocks deposited during that uplift must be preserved. Needless to say, in mountain ranges where elevations are far above sea level these criteria are not easily met. [[Paleoclimatology|Paleoclimatic restorations]] though can be valuable; these studies involve inferring changes in climate in an area of interest from changes with time of flora/fauna that is known to be sensitive to temperature and rainfall.<ref>Burbank, Douglas West., and Robert S. Anderson. Tectonic Geomorphology. Malden, MA: Blackwell Science, 2000. {{ISBN|978-0632043866}}</ref> The magnitude of the exhumation a rock has been subjected to may be inferred from [[geothermobarometry]] (measuring previous pressure and temperature history of a rock or assemblage). Knowing the pressure and temperature history of a region can yield an estimate of the ambient [[geothermal gradient]] and bounds on the exhumation process; however, geobarometric/geothermometric studies do not produce a rate of exhumation (or any other information on time). Exhumation rates can be inferred from [[Fission track dating|fission tracks]] and from [[Radiometric dating|radiometric ages]] as long as a thermal profile can be estimated.
==Gallery==
<gallery>
File:Cliffs of Moher (1542448559).jpg|[[Cliffs of Moher]]
File:Blue Mountains National Park Uplift.jpg|Tectonic uplifting in the [[Blue Mountains National Park]]
File:Tasmania Tasman National Park 5.jpg|Cliffs of the [[Tasman National Park]]
File:Horseshoe Bend 13 February 2023.jpg|[[Incised meander]] caused by downcutting of [[Colorado River]] during uplift of [[Colorado Plateau]]
File:2018 07 12 Schottland (171) Duncansby Stacks.jpg|[[Duncansby Stacks]]
File:Aerial view of 12 Apostles, Victoria, Australia (Ank Kumar) 03.jpg|[[The Twelve Apostles]]
File:Paracas National Reserve. Ica, Peru.jpg|Coast and cliffs of [[Paracas National Reserve]]
</gallery>
==References==
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