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Satellite image of the Tibetan Plateau between the Himalayan mountains to the south and the Taklamakan Desert to the north. In geology and physical geography, a plateau (/ p l ə ˈ t oʊ, p l æ ˈ t oʊ, ˈ p l æ t oʊ /; French:; pl.: plateaus or plateaux), [1] [2] also called a high plain or a tableland, is an area of a highland consisting of flat terrain that is raised sharply above the ...
Dissipation of heat from the mantle is the original source of the energy required to drive plate tectonics through convection or large scale upwelling and doming. As a consequence, a powerful source generating plate motion is the excess density of the oceanic lithosphere sinking in subduction zones.
If the viscosity of the upwelling asthenosphere is greater than that of the mantle lithosphere, delamination will stop. The upwelling asthenosphere forms two chilled, solid boundary layers on the top and bottom of the sill layer. This reduces the thickness of the portion of the lowermost crust which behaves viscously.
Upwelling intensity depends on wind strength and seasonal variability, as well as the vertical structure of the water, variations in the bottom bathymetry, and instabilities in the currents. In some areas, upwelling is a seasonal event leading to periodic bursts of productivity similar to spring blooms in coastal waters. Wind-induced upwelling ...
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.
There are five main types of mountains: volcanic, fold, plateau, fault-block, and dome. A more detailed classification useful on a local scale predates plate tectonics and adds to these categories. [ 6 ]
Continental breakup begins with rifting. When extension is persistent and entirely compensated by magma from asthenospheric upwelling, oceanic crust is formed, and the rift becomes a spreading plate boundary. If extension is isolated and ephemeral it is classified as intraplate.
With crustal extension, a series of normal faults which occur in groups, form in close proximity and dipping in opposite directions. [4] As the crust extends it fractures in series of fault planes, some blocks sink down due to gravity, creating long linear valleys or basins also known as grabens, while the blocks remaining up or uplifted produce mountains or ranges, also known as horsts.