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Plateau
Plateau
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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 (/pləˈt, plæˈt, ˈplæt/; French: [plato]; pl.: plateaus or plateaux),[1][2] also called a high plain or a tableland, is an area of highland consisting of flat terrain that is raised sharply above the surrounding area on at least one side.[3] Often one or more sides have deep hills or escarpments.[4] Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, and erosion by water and glaciers. Plateaus are classified according to their surrounding environment as intermontane, piedmont, or continental. A few plateaus may have a small flat top while others have wider ones.

Formation

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Plateaus can be formed by a number of processes, including upwelling of volcanic magma, extrusion of lava, plate tectonics movements, and erosion by water and glaciers.

Volcanic

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The Pajarito Plateau in New Mexico is an example of a volcanic plateau.

Volcanic plateaus are produced by volcanic activity. They may be formed by upwelling of volcanic magma or extrusion of lava. The underlining mechanism in forming plateaus from upwelling starts when magma rises from the mantle, causing the ground to swell upward. In this way, large, flat areas of rock are uplifted to form a plateau. For plateaus formed by extrusion, the rock is built up from lava spreading outward from cracks and weak areas in the crust. The Antrim Plateau in Northern Ireland, the Deccan Plateau in India, the Big Raven Plateau in Canada, and the Columbia Plateau in the United States are examples of lava plateaus.

Tectonic

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Tectonic plateaus are formed by tectonic plate movements which cause uplift, and are normally of a considerable size, and a fairly uniform altitude. Examples are the Deccan Plateau in India and the Meseta Central on the Iberian Peninsula.[5]

Erosion

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Plateaus can also be formed by the erosional processes of glaciers on mountain ranges, leaving them sitting between the mountain ranges. Water can also erode mountains and other landforms down into plateaus. Dissected plateaus are highly eroded plateaus cut by rivers and broken by deep narrow valleys. An example is the Scottish Highlands.[6]

Classification

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Plateaus are classified according to their surrounding environment.

Large plateaus by continent

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Africa

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The highest African plateau is the Ethiopian Highlands which cover the central part of Ethiopia. It forms the largest continuous area of its altitude in the continent, with little of its surface falling below 1,500 metres (4,921 ft), while the summits reach heights of up to 4,556 metres (14,928 ft). It is sometimes called the Roof of Africa due to its height and large area.

Another example is the Highveld which is the portion of the South African inland plateau which has an altitude above approximately 1,500 metres, but below 2,100 metres, thus excluding the Lesotho mountain regions. It is home to some of the largest South African urban agglomerations.

In Egypt are the Giza Plateau[7] and Galala Mountain, which was once called Gallayat Plateaus, rising 3,300 ft above sea level.[8]

Antarctica

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Another very large plateau is the icy Antarctic Plateau, which is sometimes referred to as the Polar Plateau or King Haakon VII Plateau, home to the geographic South Pole and the Amundsen–Scott South Pole Station, which covers most of East Antarctica where there are no known mountains but rather 3,000 m (9,800 ft) high of superficial ice and which spreads very slowly toward the surrounding coastline through enormous glaciers. The polar ice cap is so massive that the echolocation measurements of ice thickness have shown that large areas are below sea level. But, as the ice melts, the land beneath will rebound through isostasy and ultimately rise above sea level.[citation needed]

Asia

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The largest and highest plateau in the world is the Tibetan Plateau, sometimes metaphorically described as the "Roof of the World", which is still being formed by the collisions of the Indo-Australian and Eurasian tectonic plates. The Tibetan Plateau covers approximately 2,500,000 km2 (970,000 sq mi), at about 5,000 m (16,000 ft) above sea level. The plateau is sufficiently high to reverse the Hadley cell convection cycles and to drive the monsoons of India towards the south. The Deosai Plains in Pakistan are situated at an average elevation of 4,114 meters (13,497 ft) above sea level. They are considered to be the second highest plateaus in the world.

Other major plateaus in Asia are: Najd on the Arabian Peninsula, elevation 762 to 1,525 m (2,500 to 5,003 ft), Armenian Highlands (≈400,000 km2 (150,000 sq mi), elevation 900–2,100 metres (3,000–6,900 ft)), Iranian Plateau (≈3,700,000 km2 (1,400,000 sq mi), elevation 300–1,500 metres (980–4,920 ft)), Anatolian Plateau, Mongolian Plateau (≈2,600,000 km2 (1,000,000 sq mi), elevation 1,000–1,500 metres (3,300–4,900 ft)), and the Deccan Plateau (≈1,900,000 km2 (730,000 sq mi), elevation 300–600 metres (980–1,970 ft)).

North America

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A large plateau in North America is the Colorado Plateau, which covers about 337,000 km2 (130,000 sq mi) in Colorado, Arizona, New Mexico, and Utah.[9]

In northern Arizona and southern Utah the Colorado Plateau is bisected by the Grand Canyon of the Colorado River. This came to be over 10 million years ago - the river was already there, though not necessarily on exactly the same course. Then, subterranean geological forces caused the land in that part of North America to gradually rise by about a centimeter per year for millions of years. An unusual balance occurred: the river that would become the Colorado River was able to erode into the crust of the Earth at a nearly equal rate to the uplift of the plateau. Now, millions of years later, the North Rim of the Grand Canyon is at an elevation of about 2,450 m (8,040 ft) above sea level, and the South Rim of the Grand Canyon is about 2,150 m (7,050 ft) above sea level. At its deepest, the Colorado River is about 1,830 m (6,000 ft) below the level of the North Rim.

Another high-altitude plateau in North America is the Mexican Plateau. With an area of 601,882 km2 (232,388 sq mi) and average height of 1,825 metres, it is the home of more than 70 million people.

Oceania

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The Western Plateau, part of the Australian Shield, is an ancient craton covering much of the continent's southwest, an area of some 700,000 square kilometres. It has an average elevation between 305 and 460 metres.

The North Island Volcanic Plateau is an area of high land occupying much of the centre of the North Island of New Zealand, with volcanoes, lava plateaus, and crater lakes, the most notable of which is the country's largest lake, Lake Taupō. The plateau stretches approximately 100 km east to west and 130 km north to south. The majority of the plateau is more than 600 metres above sea level.

The Northern Tablelands are the largest highland area in Australia, covering approximately 18,197 square kilometres. There are widespread high points over 1,000 metres including The Brothers (1,508m), Ben Lomond (1,505m), Mount Rumbee (1,503m), Point Lookout (1,564m), Campoompeta (1,510m), Mount Spirabo (1,492m), Mount Mitchell (1,475m), Chandler's Peak (1,471m), Mount Grundy (1,462m), Mount Bajimba (1,448 m) and the highest point at Round Mountain is 1,584 metres above sea level. The now closed railway station at Ben Lomond, was the highest railway station in Australia. Apart from Antarctica it is the most extensive highland region in the Southern Hemisphere with an average elevation of over 1,000 metres.

South America

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Road to the ALMA's Operations Support Facility and then on further to the Chajnantor Plateau at 5,000 metres above sea level.[10]

The parallel Sierra of Andes delimit one of the world highest plateaux: the Altiplano, (Spanish for "high plain"), Andean Plateau or Bolivian Plateau. It lies in west-central South America, where the Andes are at their widest, is the most extensive area of high plateau on Earth outside of Tibet. The bulk of the Altiplano lies within Bolivian and Peruvian territory while its southern parts lie in Chile. The Altiplano plateau hosts several cities like Puno, Oruro, El Alto and La Paz the administrative seat of Bolivia. Northeastern Altiplano is more humid than the Southwestern, the latter of which hosts several salares, or salt flats, due to its aridity. At the Bolivia-Peru border lies Lake Titicaca, the largest lake in South America.

The Colombian capital city of Bogota sits on another Andean plateau known as the Altiplano Cundiboyacense roughly the size of Switzerland. Averaging a height of 2,600 m (8,500 ft) above sea level, this northern Andean plateau is situated in the country's eastern range and is divided into three main flat regions: the Bogotá savanna, the valleys of Ubaté and Chiquinquirá, and the valleys of Duitama and Sogamoso.

See also

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  • Atherton Tableland – Fertile plateau in northern Queensland, Australia
  • Butte – Isolated hill with steep, often vertical sides and a small, relatively flat top
  • Chapada – Plateau in the Brazilian Highlands
  • Deosai National Park – National park in Gilgit Baltistan, Pakistan
  • Mesa – Elevated area of land with a flat top and sides, usually much wider than buttes
  • Oceanic plateau – Relatively flat submarine region that rises well above the level of the ambient seabed
  • Potrero – Long mesa that at one end slopes upward to higher terrain
  • Tuya – Flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet

References

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Revisions and contributorsEdit on WikipediaRead on Wikipedia
from Grokipedia
A plateau is a prominent consisting of an extensive area of high, flat or nearly flat that rises abruptly above the surrounding , often bounded by steep slopes, cliffs, or escarpments on one or more sides. These elevated tablelands can span hundreds or thousands of square kilometers and are typically composed of resistant rock layers, such as sedimentary or volcanic materials, that have withstood better than adjacent lower areas. Plateaus represent a key category of Earth's surface features, alongside mountains, plains, and valleys, and they influence regional climates, , and patterns due to their altitude and isolation. The formation of plateaus generally involves a combination of tectonic uplift and subsequent , though processes vary by type. Tectonic plateaus, the most common variety, arise when large blocks of the are elevated through faulting or broad upwarping without significant folding, preserving relatively horizontal rock layers from ancient marine or terrestrial deposits. Volcanic plateaus form from repeated outpourings of fluid basaltic lava that spread across vast areas, cooling to create thick, flat layers, as seen in events. Over time, differential by rivers, , and carves the sharp margins and exposes the underlying structure, while the protects the surface from further degradation. Notable examples include the in the southwestern United States, a tectonic upland spanning about 390,000 square kilometers across Utah, Arizona, Colorado, and New Mexico, renowned for its colorful layered sediments and dramatic canyons like the Grand Canyon. The , often called the "Roof of the World," is the highest and largest plateau in the world, with an average elevation of over 4,500 meters and an area of approximately 2.5 million square kilometers, formed by the collision of the Indian and Eurasian plates and serving as the source for major Asian rivers such as the and Indus. Volcanic examples like the , covering parts of Washington, , and , resulted from immense eruptions between 17 and 6 million years ago, now supporting fertile agricultural lands. These diverse plateaus highlight the geological processes shaping continental interiors and their ecological and economic significance, including mineral deposits, biodiversity hotspots, and .

Definition and Characteristics

Definition

A plateau is an elevated characterized by a relatively flat or gently undulating surface that rises sharply above the surrounding on at least one side. This distinct differentiates it from adjacent lowlands, with the height difference often exceeding several hundred meters, emphasizing relative prominence over absolute altitude. Plateaus typically cover extensive areas, contributing significantly to Earth's landscape, where they account for about one-third of the planet's land surface. The term "plateau" derives from the French word plateau, meaning a flat piece of material or platter, rooted in the Middle French platel from plat (flat). Borrowed into English in the mid-18th century, its earliest recorded use dates to 1743 in a context, but it soon entered geographical and geological to denote elevated tablelands. While no strict minimum size is universally defined, plateaus are generally recognized as expansive features, often spanning hundreds of square kilometers or more, to distinguish them from smaller elevated flats like mesas. Historical recognition of plateaus as key geological features emerged in the late 18th and early 19th centuries amid European exploration and scientific mapping. Naturalist provided one of the early detailed descriptions during his 1799 travels through , where measurements confirmed the Iberian Peninsula's character as a vast plateau averaging around 600 meters in elevation. His observations, integrated into broader works on , helped establish plateaus as fundamental elements in understanding distribution and gradients.

Key Physical Features

Plateaus are characterized by broad, relatively flat or gently inclined surfaces with minimal topographic relief, typically featuring variations of less than 100 meters across their tops, which distinguishes them from more rugged highland features. This flatness arises from the dominance of horizontal or near-horizontal rock strata that resist uniform , creating expansive table-like landforms often capped by durable layers that protect underlying materials. For instance, the exemplifies this with its vast, even-surfaced expanses formed by layered sedimentary rocks. The boundaries of plateaus are typically defined by steep edges or escarpments, such as cuestas or scarps, where the drops abruptly to surrounding lower , with vertical ranging from 100 to 1000 meters. These steep margins result from differential along the plateau's perimeter, exposing resistant rock faces that form dramatic cliffs or slopes. The , for example, features prominent escarpments like the Scarps, which rise sharply hundreds of meters above adjacent valleys. Drainage on plateaus is often limited and internal, leading to endorheic basins where water collects without reaching the sea, or radial patterns that direct flow outward from a central high point; however, perennial rivers can incise deeply into the surface, carving canyons and gorges. The demonstrates endorheic drainage with closed basins like those feeding the Qaidam Lake, while river incision is evident in the Colorado Plateau's , where the has cut through over 1,600 meters of strata. The rock composition of plateaus predominantly consists of erosion-resistant sedimentary, volcanic, or crystalline rocks, which contribute to their stability and distinctive morphology. Sedimentary rocks like sandstones and limestones form many continental plateaus, while volcanic plateaus such as the Columbia Plateau are built from thick basalt flows; crystalline rocks, including granites, underlie some elevated regions like parts of the Brazilian Plateau. These materials vary in durability but collectively support the plateau's elevated, flat profile. Plateau layers, particularly the resistant cap rocks or individual formations, are typically 100 to 500 meters thick, providing structural integrity that influences long-term stability against . In the , formations like the reach thicknesses of around 200-300 meters, acting as protective caps over softer underlying strata.

Distinction from Mountains and Plains

Plateaus are distinguished from mountains primarily by their extensive, relatively flat summits and low local relief, in contrast to the peaked, irregular and high relief characteristic of mountains, which often feature steep slopes and elevations rising prominently due to tectonic processes like compression and uplift. Unlike , which are broad, low-lying expanses of gently sloping or flat formed by deposition or at low elevations, plateaus rise sharply above their surroundings, typically by several hundred meters, and are bounded by abrupt escarpments or steep margins. Plateaus also differ in scale from related landforms such as mesas and ; while plateaus cover large areas with flat tops and cliffs on one or more sides, mesas are smaller, isolated flat-topped elevations wider than they are tall, and buttes are even narrower, pillar-like features taller than wide, with no universally agreed size threshold but generally distinguishing plateaus as more extensive (often exceeding several square kilometers). The term "tableland" is frequently synonymous with plateau, referring to elevated flat terrain, though it sometimes specifically denotes more arid or dissected variants with irregular surfaces due to . A common misconception is that any elevated flat surface qualifies as a plateau; in reality, features like —gently undulating, low-relief erosional plains formed near base level without steep bounding margins—lack the sharp elevation contrast essential to true plateaus.

Formation Processes

Tectonic Formation

Tectonic plateaus form primarily through the uplift of extensive crustal blocks driven by plate tectonic forces, including continental collisions, , and rifting, which cause broad arching of the without intense folding or in the central regions. This process often involves crustal thickening from compressional stresses, leading to isostatic adjustment where the buoyant, thickened crust rises to maintain equilibrium. In cases of -related , flat-slab can transmit far-inland compression, elevating rigid crustal sections over vast areas. Key processes include orogenic uplift, where tectonic compression builds elevated terrains, followed by limited that preserves the flat-topped morphology, especially over stable cratonic interiors that resist deformation due to their ancient, rigid composition. Isostatic rebound contributes when eroded material or delaminated lower reduces load, allowing the crust to rise further; rifting can also initiate uplift by thinning adjacent areas and creating relative highs. These dynamics are exemplified in the role of rigid cratons, which form the stable cores of many plateaus by undergoing minimal deformation during subsequent tectonic events. The timeline for tectonic plateau formation is typically protracted, often initiating in the era over billions of years, with major uplift phases occurring during orogenies spanning tens of millions of years. For instance, shields like the Laurentian Plateau () represent ancient uplifted cratons that stabilized after early Earth assembly, with recent minor rebound continuing into the . Geological evidence for tectonic plateaus includes fault-block structures at margins, such as horsts and grabens, and gently tilted or horizontal strata indicating post-uplift stability. The provides a classic example, uplifted during the from approximately 70 to 40 million years ago through compression from flat-slab subduction of the Farallon plate, resulting in broad arching of basement overlain by undeformed sedimentary layers. This event produced minimal internal deformation, with evidence seen in the plateau's elevated, intact stratigraphic sequences and peripheral fault systems. Associated features often include marginal grabens or horsts formed during initial rifting or extension phases, which delineate the plateau boundaries and precede broader uplift.

Volcanic Formation

Volcanic plateaus arise from the massive outpouring of low-viscosity basaltic during events, where eruptions occur along extensive fissures rather than centralized vents, enabling lava to flow and accumulate over vast horizontal distances. This mechanism, known as continental flood volcanism, produces broad, relatively flat expanses through successive layers of thin, widespread flows that solidify into thick sequences without significant topographic relief during formation. The primary processes involve the development of trap formations, characterized by stacked, horizontal sheets of that result from repeated effusive eruptions. As these thick lava flows cool slowly from the base upward, thermal contraction induces fracturing into polygonal prisms or columns, observable on a grand scale in features akin to the in , where from ancient fissure eruptions formed over 40,000 interlocking hexagonal columns. Geological evidence for these plateaus includes nearly horizontal layers typically 1 to 2 kilometers thick, interspersed with thinner ash beds and sedimentary intertrappean deposits that mark pauses between eruptions. Such plateaus form rapidly, often over spans of thousands to less than a million years, followed by long-term stabilization as the volcanic activity wanes. A prominent example is the in , which erupted around 66 million years ago in pulses lasting approximately 700,000 to 800,000 years, covering roughly 500,000 square kilometers with an estimated volume exceeding 1 million cubic kilometers of material. Volcanic plateaus are broadly classified into continental flood basalt types, exemplified by the and the Basalts in , and shield volcano plateaus, which develop from the coalescence of multiple low-angle es built by fluid lava flows, such as the submarine Hawaiian Plateau. These formations often occur in tectonic settings like mantle plumes or rift zones that facilitate the ascent of voluminous .

Erosional Formation

Erosional plateaus form primarily through differential erosion, a process where softer rock layers are worn away more rapidly than underlying or overlying resistant strata, resulting in elevated, flat-topped landforms capped by durable materials such as or conglomerate. This subtractive mechanism typically occurs after initial tectonic uplift elevates the region, exposing it to prolonged surface processes that strip away less resistant sediments. For instance, in the , a resistant cap of Rockcastle Conglomerate protects softer and shales below, preserving the elevated surface while surrounding areas erode away. The key processes driving erosional plateau formation include river downcutting, chemical and physical , and , often preceded by the development of broad, low-relief surfaces known as pediplains or etchplains through extended under stable conditions. Rivers incise deep valleys into the uplifted terrain, accelerating erosion by transporting downstream, while breaks down rock at the surface and along joints, and events like landslides remove large volumes of material from steepened margins. These processes operate slowly over tens of millions of years, with the post-uplift phase dominating the landscape evolution; for example, the 's major entrenchment by the began around 5 million years ago following uplift. Geological evidence of erosional formation includes dissected margins with incised canyons and gorges, as well as inverted relief where former valleys in softer rocks are transformed into prominent ridges due to differential of adjacent harder layers. The exemplifies this, where sedimentary rocks, uplifted during the late , have been deeply carved by streams into a rugged of parallel ridges and valleys, with exposing flat-lying strata over 300 million years. Such features highlight the long-term dominance of fluvial and hillslope processes in sculpting these landforms. Erosional plateaus are classified into dissected and undissected types based on the degree of incision and relief. Dissected plateaus, like the Appalachian and Colorado Plateaus, exhibit sharp relief from extensive river carving and valley development, creating a mountainous appearance despite their plateau origins. In contrast, undissected erosional plateaus retain more intact, gently sloping surfaces with minimal deep incision, such as portions of the in , where resistant caps limit and preserve broader flatness.

Classification

By Origin

Plateaus are classified by origin according to the dominant geological process that primarily shaped their elevated, relatively flat , allowing geologists to trace their genetic history. This genetic emphasizes the initial formative mechanism, though plateaus often evolve through superimposed processes, such as initial uplift followed by , leading to transitions between categories over millions of years. Tectonic-origin plateaus result from the uplift of crustal blocks or warping due to plate boundary interactions, including compressional folding, faulting, or extensional rifting that elevates large sections of the . These form when horizontal stresses cause vertical displacement, creating broad elevated surfaces without significant volcanic input. Volcanic-origin plateaus develop through the repeated and accumulation of basaltic lava from vents or volcanoes, building thick layers that solidify into flat expanses. This process dominates in regions of widespread mafic , where fluid lavas spread over vast areas before cooling. Erosional-origin plateaus emerge as elevated remnants of formerly more extensive highland surfaces sculpted by prolonged and fluvial incision, preserving resistant caprocks atop softer substrates. These represent the end product of on uplifted terrains, where differential isolates flat-topped residuals. Plateaus of mixed or other origins arise from combined processes, such as interactions in stable continental interiors, or rarer mechanisms like glacial followed by isostatic rebound, though these constitute a minor subset where no single process clearly predominates. relies on stratigraphic, structural, and geomorphic evidence to identify the controlling origin, with ongoing or tectonism potentially shifting a plateau's category in subsequent geological epochs.

By Morphology and Elevation

Plateaus can be classified based on their morphology, which encompasses their shape, slope characteristics, and surface uniformity, as well as their relative to surrounding landscapes. This classification highlights how these features influence local and environmental conditions, distinct from their formation origins, though tectonic or erosional processes may contribute to their overall profile. Intermontane plateaus are situated between mountain ranges, often exhibiting steep escarpments on multiple sides and moderate elevations typically ranging from 500 to 2000 meters above . These plateaus form enclosed basins that trap s and promote unique drainage patterns. Piedmont plateaus occur at the base of mountain ranges, characterized by transitional slopes that gently descend toward adjacent plains or lowlands, with elevations generally lower than intermontane types due to their depositional nature. This morphology results in a gradual incline, facilitating accumulation from uphill . Continental plateaus occupy vast interiors of continents, surrounded by plains or , and are marked by relatively high elevations exceeding 1500 meters, with abrupt rises along their margins. Their broad, elevated surfaces often reflect ancient uplift events preserved over large areas. Morphologically, plateaus may present as stepped subtypes, featuring tiered levels or multiple flat benches separated by escarpments, or as uniform subtypes with a consistently even, horizontal surface. Stepped morphologies arise from differential or successive uplift phases, while uniform ones maintain a more monolithic flatness. Elevation further influences plateau characteristics, with higher elevations fostering cooler temperatures, altered precipitation patterns, and distinct biodiversity due to reduced atmospheric pressure and increased solar radiation exposure. These elevational differences significantly modulate regional climate dynamics, such as intensifying monsoon effects or creating rain shadows.

By Size and Dissection

Plateaus are classified by size based on their areal extent and by the degree of surface dissection, which quantifies the incision by fluvial and erosional features. Size categories delineate small plateaus as those covering less than 1,000 km², often resembling mesas with limited lateral spread; medium plateaus spanning 1,000 to 10,000 km², providing intermediate scales of flat terrain; and large plateaus exceeding 10,000 km², which dominate regional landscapes. For instance, the Mesa Verde mesa in Colorado exemplifies a small plateau at approximately 211 km², while the Yellowstone Plateau represents a large one at approximately 6,500 km². Dissection levels further refine this classification, ranging from undissected plateaus with largely intact, flat surfaces and minimal valley incision to moderately dissected ones featuring shallow valleys and low-relief drainage patterns, and highly dissected plateaus marked by deep canyon networks and sharp relief. The offers examples of relatively undissected volcanic surfaces in its central regions, where basalt flows remain broadly preserved. In contrast, the illustrates high dissection through its extensive canyon systems, such as the Grand Canyon, resulting from prolonged fluvial erosion. Plateau areas are measured using satellite imagery and geographic information systems (GIS) to delineate boundaries and compute extents accurately. Dissection is quantified via the dissection index, derived from valley density metrics like drainage density (total stream length per unit area) or the ratio of relative relief to absolute relief, which indicates the intensity of surface cutting. These classifications carry geological implications: larger plateaus tend to exhibit greater long-term stability, with reduced deformation compared to surrounding regions, as evidenced by the 's resistance to faulting amid adjacent tectonic activity. Highly dissected plateaus, conversely, often reflect younger or more dynamically active settings, where recent tectonic uplift has intensified erosional dissection of the surface. This dissection arises from erosional processes that carve uplifted terrains over time.

Major Plateaus by Region

African Plateaus

The African continent features several prominent plateaus, shaped by tectonic rifting, volcanic activity, and erosional processes, which collectively influence regional and . These elevated landforms, often exceeding 1,000 meters in height, cover vast areas and host unique geological features that contribute to Africa's diverse landscapes. The East African Plateau, spanning parts of , , , and southern , represents one of the continent's largest elevated regions, with an approximate area of 2 million square kilometers. It owes its formation primarily to volcanic processes associated with the system, where mantle upwelling has produced extensive basalt flows and shield volcanoes over the past 23 million years. Elevations across the plateau typically range from 1,000 to 2,000 meters, creating a broad, undulating highland dissected by the , a series of grabens formed by crustal extension. This , marked by active faulting and ongoing , bisects the plateau and gives rise to features like the Ngorongoro Crater and . In , the South African Plateau, commonly known as the , forms a tectonically uplifted and erosional surface averaging around 1,500 meters in elevation, extending across much of , , and parts of . Its geology reflects ancient tectonic stabilization of the followed by prolonged erosion that exposed remnants of the Karoo Basin, a vast -Mesozoic sedimentary sequence filled with glacial, fluvial, and coal-bearing deposits up to 5 kilometers thick in places. The plateau's formation involved Gondwanan subduction-related compression in the Late , succeeded by epeirogenic uplift and scarp retreat, resulting in a stepped with escarpments like the . The , located in the , constitute a massive volcanic province rising to elevations of up to 3,000 meters and covering over 1 million square kilometers, making it one of the highest and most extensive plateaus in . Formed by eruptions during the Oligocene-Miocene, linked to the Afar hotspot and early rifting, the highlands feature thick layers of trap basalts that create dramatic canyon systems through which major rivers incise. , the primary source of the , lies within this elevated terrain at approximately 1,800 meters, feeding the river's dramatic descent through the highlands' deeply eroded gorges. Within the Ethiopian Highlands, the Sanetti Plateau in the Bale Mountains spans thousands of square kilometers at elevations around 3,000 meters, supporting afro-alpine grasslands, shrubs, and unique flora such as giant lobelia, with nearby human settlements like the town of Goba engaging in farming activities. African plateaus exert significant influence on continental climate patterns, particularly through rain shadow effects where elevated barriers block moist air masses, leading to drier conditions on leeward sides; for instance, the East African Plateau's highlands contribute to aridity in the Tanzanian interior. These regions also serve as biodiversity hotspots, exemplified by the Serengeti ecosystem on the East African Plateau, which supports one of the highest concentrations of large mammals in due to its volcanic soils and varied grasslands.

Asian Plateaus

Asia's plateaus are among the most extensive and tectonically dynamic landforms on , shaped primarily by continental collisions and volcanic activity along active plate boundaries. These features span vast areas, influencing regional climates and seismic patterns, with the standing out as the highest and largest. The , often called the "," covers approximately 2.5 million km² and has an average elevation exceeding 4,500 m, making it the world's highest plateau. It formed through the ongoing collision between the Indian and Eurasian plates, which began around 50 million years ago, compressing and thickening the continental crust to produce this elevated expanse. This tectonic process has resulted in intense seismic activity across the plateau, as strain accumulates along the plate boundary. The plateau features deep, glacier-fed lakes such as Migriggyangzham and Dorsoidong, and is home to populations adapted to high-altitude living. In southern India, the Deccan Plateau extends over about 500,000 km² with elevations typically ranging from 600 to 900 m, formed by massive outpourings of lava during the , known as the . These volcanic floods, exceeding 2,000 m in thickness in places, created a relatively flat, stepped terrain that experiences strong seasonal influences, shaping its and . The , averaging around 1,000 m in elevation and framed by the to the southwest, occupies a spanning roughly 1.5 million km². Its uplift stems from the Arabia-Eurasia collision, involving and crustal shortening that has produced an arid interior with folded mountain belts. Seismic risks are elevated here due to ongoing convergence at the plate boundary. A key tectonic nexus in is the Pamir Knot, where multiple mountain ranges—including the Pamirs, , , and —converge, acting as a hub that links several high plateaus and channels seismic energy from Indo-Eurasian interactions. This junction exemplifies the broader of Asian plateaus, driven by active plate boundaries that continue to deform the crust.

North and South American Plateaus

The , located primarily in the spanning parts of , , , and , is a prominent erosional plateau covering approximately 390,000 square kilometers. Its elevations generally range from 1,500 to 3,000 meters, with a mean elevation of 1,936 meters, shaped by differential of layered sedimentary rocks over millions of years, resulting in dramatic landscapes such as deep canyons and mesas. The , carved by the , exemplifies this erosional history, exposing nearly 2 billion years of geological strata within the plateau's resistant rock layers. This region has significant mineral resources, including deposits in sandstone-hosted ores, which have been mined extensively since the mid-20th century, contributing over 1.2 billion pounds of . The plateau supports diverse ecosystems, from arid shrublands at lower elevations to montane forests at higher altitudes. Further north, the in the , encompassing parts of Washington, , and , represents a vast volcanic formation dominated by thick layers of from massive flood eruptions between 17 and 6 million years ago. Covering about 164,000 square kilometers, it features elevations ranging from 600 to 1,800 meters, with the flat to gently rolling terrain resulting from the accumulation of over 170,000 cubic kilometers of Columbia River Basalts. These basaltic flows, up to 1,800 meters thick in places, were erupted through fissures and later modified by erosion from the and its tributaries, creating the scenic . In , the stands as the second-largest high plateau outside , formed through tectonic processes associated with the uplift of the Mountains, and spans portions of , , and with an area of roughly 200,000 square kilometers. Situated at an average elevation of about 3,800 meters, it consists of intermontane basins between the Andean cordilleras, where compressional forces from the of the Nazca Plate beneath the South American Plate have elevated ancient sedimentary and volcanic rocks. , the largest freshwater lake in by volume, occupies the northern basin at 3,812 meters elevation, serving as a key hydrological feature amid the plateau's arid to semi-arid conditions. The has profoundly influenced South American plateaus like the , creating a that enhances its high-altitude isolation and endorheic drainage patterns. The region was historically home to the Inca Empire and today supports human settlements adapted to the high-altitude environment. The , also known as the Brazilian Highlands, occupies a significant portion of eastern and central , covering over 3 million square kilometers of ancient shield rocks that have undergone extensive erosion since the era. With elevations typically between 600 and 1,200 meters, it features undulating terrain of low mountains, escarpments, and planation surfaces developed on crystalline basement rocks dating back to 2.5 billion years ago. This erosional landscape, resistant to weathering due to its granitic and gneissic composition, contrasts with surrounding sedimentary basins and supports diverse ecosystems shaped by tropical weathering processes. It is the largest plateau in South America in terms of natural resources and human settlement, with major population centers along its coastal fringe.

Plateaus in Europe, Australia, and Antarctica

In , plateaus are generally smaller and more fragmented compared to those in other continents, often shaped by a combination of volcanic activity, tectonic uplift, and extensive glacial modification. The in south-central exemplifies a volcanic plateau, formed by Cenozoic alkaline volcanism overlying Variscan basement rocks, with elevations ranging from approximately 800 to 1,800 meters. This upland region features chains of basaltic and trachytic cones, maars, and lava domes, resulting from rift-related magmatism that has persisted into the . Further west, the Iberian Meseta represents a classic erosional plateau, primarily developed through Mesozoic-Cenozoic of the Iberian plate following tectonic compression and uplift associated with the . Spanning about 300,000 square kilometers across central and , it has an average elevation of around 600 to 700 meters, divided into northern and southern sectors by the Central System mountain range. In northern Europe, the Hardangervidda Plateau in Norway is the largest mountain plateau on the continent, covering extensive areas of highland terrain shaped by glacial processes. Many European plateaus, including parts of the and surrounding Hercynian uplands, exhibit deep dissection from Pleistocene glaciations, where ice sheets drove widespread across high-elevation surfaces far beyond confines, creating rugged terrains with U-shaped valleys and cirques. Australia's plateaus are dominated by ancient, stable cratonic structures in the interior, reflecting billions of years of minimal tectonic disturbance. The , encompassing the bulk of , is a tectonic formed on cratons such as the Yilgarn and blocks, with low relief typically between 300 and 600 meters and occasional highs exceeding 800 meters. Covering roughly 50% of the continent, this vast, low-gradient surface consists of weathered granitic and metamorphic rocks overlain by lateritic soils, isolated by surrounding arid basins and contributing to the continent's overall through limited drainage and high rates. In , plateaus are obscured beneath immense s but play a critical role in global climate regulation. The , largely ice-covered and forming the core of the , underlies a surface at elevations averaging about 3,000 meters above , with rising even higher in places, and represents one of the world's largest plateaus spanning millions of square kilometers. This expansive feature, spanning millions of square kilometers in a hyper-arid environment receiving less than 50 millimeters of annual , remains largely inaccessible due to extreme cold and logistical challenges. Its stability stems from resting on elevated subglacial , mitigating rapid responses to warming and influencing ice sheet dynamics by sourcing slow-flowing outlet glaciers that buttress coastal margins.

Ecological and Human Dimensions

Climate, Geology, and Biodiversity

Plateaus exhibit diverse climate patterns largely influenced by their elevated and position relative to prevailing wind systems. Rain shadows, formed when moist air is forced upward by plateau margins and loses on the windward side, often result in arid conditions on the leeward side. For instance, the lies within Earth's largest , created by the , affecting the and contributing to the region's cold, arid with limited annual . Similarly, the Himalayan-Tibetan complex enhances this effect, leading to drier conditions across . Altitudinal zonation on plateaus creates distinct and belts, transitioning from lower-elevation s to higher tundra-like environments due to decreasing temperatures and increasing exposure with elevation. In regions like the , these zones shift upward southward, with and open woodlands at mid-elevations giving way to subalpine forests and above timberline. On the Central , elevations exceeding 5,000 meters support sparse alpine and meadow in a cold, arid setting, while lower areas feature more continuous grasslands. Central Asian plateaus display similar profiles, with subtypes below periglacial tundra zones shaped by temperature gradients. Geological composition significantly influences and fertility on plateaus, affecting productivity. Basaltic parent materials, common in volcanic plateaus, weather into finely textured soils rich in nutrients like and iron oxides, supporting fertile conditions for growth. In contrast, crystalline rock substrates, such as those in granitic or gneissic plateaus, produce acidic, nutrient-poor soils that favor acid-tolerant plants with low fertility demands, limiting overall . Isolation imposed by plateau topography promotes , as geographic barriers restrict and foster . On the Qinghai-Tibetan Plateau, intra-plateau glacial refugia during past cold periods have driven the evolution of endemic lineages, particularly in areas, contributing to high uniqueness. In mountainous plateaus like the Iranian ranges, elevational gradients and isolation correlate with increased endemism rates for and animals. Biodiversity on plateaus is often highest in undissected, expansive areas where continuous habitats support diverse assemblages. The ' montane grasslands, spanning 1,500–3,000 meters, harbor rich and , including endemic adapted to highland conditions. Andean páramos, high-elevation wetlands above 3,000 meters, exhibit exceptional , with over 86% of flowering unique to the and supporting diverse birds, amphibians, and . Australian plateaus, such as those in the Southwest Woodlands, feature eucalypt-dominated systems with hotspots of plant richness, including over 3,500 , many endemic to the jarrah-marri forests. Dissection through erosion or human activity fragments plateau habitats, posing threats to by isolating populations and reducing genetic diversity. Such fragmentation increases , elevates extinction risks for specialist , and disrupts ecological connectivity in once-contiguous areas. glaciations have profoundly shaped current plateau biomes by alternating cold, dry phases with warmer interglacials, influencing distribution and . On the , these cycles drove shifts from to more open, arid communities, with glacial advances creating refugia that preserved endemic biota. In North American plateaus like Yellowstone, Pleistocene ice sheets enhanced topographic and development, establishing modern tundra- transitions. These historical dynamics underscore the resilience and vulnerability of plateau ecosystems to climatic variability.

Economic Uses and Cultural Importance

Plateaus have long been vital for human economic activities due to their resource-rich substrates and relatively flat terrains, which facilitate extraction and utilization. In , the Plateau in is renowned for its extensive deposits, which have historically driven the global market and contributed significantly to the country's ; the holds a significant share of the world's gold reserves, with accounting for about 10% of global reserves as of 2023 (approximately 6,000 metric tons out of 59,000 metric tons worldwide), mining operations dating back to the late 19th century. Similarly, in , the hosts major oil and gas reserves, where formations have enabled hydraulic fracturing techniques to boost U.S. production, accounting for a substantial portion of domestic output since the 2000s. Agriculture also thrives on volcanic plateaus, as seen in the of the , where fertile soils support cultivation, a staple crop that sustains indigenous communities and contributes to regional . development leverages the steep escarpments surrounding plateaus, with projects like those on the generating electricity for , harnessing the dramatic elevation drops to produce that powers industrial growth. Transportation infrastructure benefits from the expansive, level surfaces of plateaus, though their abrupt margins pose engineering challenges. The Trans-Siberian Railway traverses the Central Siberian Plateau, spanning over 9,000 kilometers and facilitating trade between Europe and Asia since its completion in 1916, which has been crucial for resource export like timber and minerals. However, the steep edges of plateaus often require costly tunneling and bridging, as exemplified by routes crossing the Deccan Plateau in India, which supported ancient trade caravans along the Silk Road extensions and modern highways connecting ports to inland markets. Culturally, plateaus hold profound significance for indigenous and religious communities, shaping spiritual and social practices. The serves as a sacred landscape in , with sites like revered as a pilgrimage center, influencing monastic traditions and cultural identity for millions. In the Andean plateaus, the Inca developed sophisticated terracing systems to adapt agriculture to high-altitude conditions, creating agricultural landscapes that integrated with spiritual beliefs in , the earth mother, and remain in use today. Historically, the facilitated ancient trade routes that exchanged spices, textiles, and ideas between and the , fostering cultural exchanges evident in rock-cut temples and linguistic influences. In modern contexts, plateaus face urbanization pressures and conservation needs. Mexico City, situated on the Valley of Mexico basin plateau, exemplifies rapid urban expansion, where the plateau's isolation has concentrated over 20 million residents, driving economic hubs in manufacturing and services but straining . Post-2000 conservation efforts, such as those in the through the U.S. , aim to balance economic uses like with protection, addressing threats to from and development.

References

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