Plateaus of South America

Plateaus of South America
Name	Plateaus of South America
Location	South America

Plateaus of South America offer a mosaic of elevated landforms that shape hydrology, climate, and human settlement across Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela, and neighboring states. These uplands—ranging from the high, cold expanses of the Altiplano to the tropical tepuis of the Guiana Highlands—anchor river systems such as the Amazon River and the Paraná River while intersecting with mountain systems like the Andes. Plateaus have been central to pre-Columbian polities, colonial administrations, and modern nation-state development, influencing infrastructure projects such as the Trans-Amazonian Highway and natural-resource policies in institutions like Petróleos de Venezuela and Petrobras.

Overview and Definition

A plateau is an elevated, relatively flat region; in South America these features include intermontane basins, volcanic mesas, and sandstone tablelands such as the Tepuis. Prominent categories include the high plateaus of the Altiplano and the low plateaus of the Brazilian Highlands, which extend across Minas Gerais, São Paulo, and Bahia. Other recognized plateaus are the Patagonian Plateau in Argentina, the Puna de Atacama in Chile and Argentina, and the Guiana Shield formations in Venezuela, Guyana, and Suriname. Plateaus often underlie major drainage divides like the Continental Divide, feed basins such as the Orinoco Basin, and host urban centers including La Paz, Lima, and Quito.

Major Plateaus by Region

The Andean highlands center on the Altiplano between La Paz and Potosí in Bolivia and extend into Peru and Argentina. The southern cone contains the Patagonian Plateau and the volcanic plateaus of Neuquén and Mendoza in Argentina, adjacent to features like the Chilean Lake District. The Brazilian interior is dominated by the Brazilian Highlands and the Cerrado, intersecting provinces like Goiás and Mato Grosso, and bounded by coastal ranges such as the Serra do Mar and the Espinhaço Range. Northern South America hosts the Guiana Highlands with tepuis including Mount Roraima and Auyán-tepui in Bolívar; these plateaus feed the Orinoco River and support ecosystems around Angel Falls. The western cordillera contains intermontane plateaus like the Puna and volcanic plateaus of the Altiplano Cundiboyacense in Colombia near Bogotá.

Geology and Formation

Plateau formation in South America reflects precambrian cratons such as the Guiana Shield and the Brazilian Shield, Phanerozoic orogeny tied to the Andean orogeny, and Meso-Cenozoic volcanism associated with the Nazca Plate subduction beneath the South American Plate. Tepuis are remnants of the Roraima Group sandstone atop the Guiana Shield and preserve ancient strata older than formations in the Amazon Basin. The Altiplano evolved via crustal shortening during the Andean uplift and subsequent crustal thickening evident near the Altiplano–Puna plateau volcanic complex. Basaltic plateaus in the southern cone relate to the Paraná Flood Basalts and magmatic provinces that include Iguaçu flows, while erosional plateaus in the Brazilian Highlands result from weathering of the Precambrian shield.

Climate and Ecology

Climatic regimes over plateaus vary from high-altitude alpine conditions on the Altiplano—influenced by El Niño–Southern Oscillation variability—to humid tropical climates atop tepuis that nurture endemic flora near Roraima National Park. The Brazilian Highlands house the Cerrado savanna and transitional forests adjacent to the Atlantic Forest ecoregion, hosting biodiversity hotspots recognized by conservation programs of organizations such as the World Wide Fund for Nature. The Patagonian Plateau supports steppe and cold-desert biomes tied to the Southern Annular Mode, while Andean puna grasslands sustain species adapted to hypoxia and UV exposure, seen in fauna from vicuña to highland waterfowl.

Human History and Cultural Significance

Plateaus have long been centers of human activity: the Tiwanaku and Inca Empire established agricultural and ceremonial systems across the Altiplano, utilizing terraces and irrigation near sites like Tiwanaku (archaeological site) and Machu Picchu. Colonial mining hubs such as Potosí transformed imperial economies under the Spanish Empire, and missionary routes crossed the Guiana Highlands during the era of the Catholic Church missions. Modern indigenous nations, including the Aymara, Quechua, and Yanomami, maintain cultural landscapes on plateaus, engaging with contemporary politics in capitals like La Paz and institutions including the Organization of American States.

Economic Resources and Land Use

Plateaus host mineral wealth—silver and tin in Potosí, copper deposits adjacent to Antofagasta, iron ore in Minas Gerais, and bauxite in parts of the Guiana Shield—which attract multinational firms such as Vale (company) and Glencore. Hydrocarbons in the Orinoco Belt and onshore basins drive extraction by companies like Petróleos de Venezuela and regional producers, while highland agriculture produces quinoa, potatoes, and livestock integral to rural economies in Peru and Argentina. Hydroelectric projects on plateau-fed rivers, exemplified by large dams near Itaipu and Andean reservoirs, interface with infrastructure networks including the Trans-Andean railway and regional trade corridors.

Conservation and Environmental Issues

Environmental concerns on South American plateaus include deforestation in the Cerrado and Amazon Rainforest corridors, mining impacts in Potosí and Carajás, and water-resource pressures on the Altiplano exacerbated by glacial retreat linked to climate change. Conservation initiatives span protected areas such as Sierra Nevada de Mérida National Park, Mount Roraima National Park, and biosphere reserves designated by the UNESCO World Heritage Centre. Conflicts arise among extractive industries, indigenous land rights litigated in courts of Brazil and Colombia, and multilateral environmental agreements negotiated within forums like the United Nations Framework Convention on Climate Change.

Category:Plateaus Category:Landforms of South America