| For alternate uses of the term, see Plateau
(disambiguation).
In geology and earth
science, a plateau is an area of highland, usually consisting of relatively flat open country if the uplift was recent in
geologic history. Plateaus, like mesas and buttes, are formed when land has been uplifted by tectonic activity and then eroded by wind or water. Flat-topped, sheer-sided plateaus, like the
tepuis of Guiana, are formed when a section of
land is uplifted that is topped with a layer of particularly resistant rock, and underlain by softer rock.
Plateau is also used to describe undersea geologic formations. Some undersea plateaus, like the Seychelles plateau, are fragments of continental crust that lie separate from
continents; they are analogous to continental shelves, but
without the continents. Some, like the Seychelles, have peaks that rise from the sea as islands; others rest entirely below the
surface. Other undersea plateaus were formed by outpourings of flood basalts, and were
never associated with continents; the vast Ontong Jaya Plateau of the western Pacific is an example of such.
Examples of plateaus
The Tibetan plateau is one of the most famous examples of this
landform, but there are many other notable examples of it from around the world, including:
A more complete list of plateaus is available.
Dissected plateaus
A highly eroded plateau is called a dissected plateau. These
older uplifts have been eroded by creeks and
rivers to develop steep relief not immediately distinguishable from mountains. Many areas of the Allegheny Plateau and the Cumberland
Plateau, which are at the western edge of the Appalachian
Mountains of eastern North America, are called "mountains" but are
actually dissected plateaus. One can stand on a high "mountain" and note that all the other tops are at the same height, which
represents the original plain before uplift.
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