This article was accepted into the corpus but its outbound wikilinks were never NER-processed — typical at the deepest BFS hop or when the run's entity cap was reached. No expansion funnel to show.
| Geology of South America | |
|---|---|
| Name | Geology of South America |
| Caption | Andes from space |
| Region | South America |
Geology of South America describes the rock record, tectonic evolution, magmatism, and sedimentary basins of the South American continent from the Precambrian to the present. The continental crust records interactions among the South American Plate, Nazca Plate, Caribbean Plate, and fragments of West Gondwana assembly, producing major provinces such as the Amazonian Craton, Guiana Shield, and the Andes. Research from institutions like the Smithsonian Institution, United States Geological Survey, and universities across Brazil, Argentina, and Chile has integrated geochronology, structural geology, and paleontology to resolve episodes of collision, rifting, and Andean uplift.
South America's evolution began with Archean and Proterozoic growth of cratons including the Amazonian Craton, São Francisco Craton, Río de la Plata Craton, and the Guiana Shield, later assembled during the Brasiliano orogeny and Grenville orogeny-related events. The breakup of Gondwana in the Mesozoic formed the South Atlantic opening between Brazil and Angola, connecting rifting to the emplacement of Paraná-Etendeka flood basalts and the formation of the Pelotas Basin and Salado Basin. Cenozoic plate convergence with the Nazca Plate drove the Andean orogeny, reshaping drainage systems like the Amazon River and creating foreland basins such as the Marañón Basin and Neuquén Basin.
The continental margin is dominated by the active convergent boundary of the Nazca Plate subducting beneath the western margin of the South American Plate, producing the Peru–Chile Trench, the Andean Volcanic Belt, and frequent seismicity recorded by agencies such as the USGS and Observatorio Volcanológico de los Andes del Sur. To the north, interactions with the Caribbean Plate and microplates including the North Andes Plate and Malpelo Plate complicate deformation across Colombia and Venezuela. The eastern margin exhibits a passive margin along the South Atlantic Ocean with volcanic passive-margin sequences tied to mid-Atlantic Ridge spreading and the Camamu Basin and Abrolhos Bank records.
Distinct provinces include ancient shields like the Amazonian Craton and Guiana Shield, orogenic belts such as the Andes and the Brasiliano Belt, and composite terranes accreted during Paleozoic–Mesozoic collisions, for example the Pampia Terrane and the Cuyania Terrane. The Falkland Islands block and the Chilean Coastal Range represent displaced terranes and magmatic arcs linked to subduction dynamics. Offshore, the Falkland Plateau and Río de la Plata Craton margins preserve rifted continental fragments recorded in seismic profiles collected by institutions like the British Geological Survey.
Stratigraphic architecture spans Archean gneisses through Proterozoic greenstone belts to Phanerozoic sedimentary sequences preserved in basins such as the Amazon Basin, Neuquén Basin, Guanabara Basin, Magallanes Basin, and the Banda Oriental Basin. Mesozoic rift-related successions host hydrocarbon systems in the Campos Basin and Santos Basin offshore Brazil, with source rocks correlated to Paleogene and Cretaceous intervals. Fluvial and lacustrine deposits of the Solimões Formation and the Ituzaingó Formation record paleoenvironmental shifts tied to Andean uplift and eustatic changes influenced by events like the Eocene–Oligocene extinction and climatic shifts captured in cores studied by the International Ocean Discovery Program.
Subduction along the western margin generated magmatism forming the Andean Volcanic Belt, with volcanic centers such as Ojos del Salado, Cotopaxi, Tungurahua, Villarrica, and Llaima. The Andean orogeny produced crustal shortening, uplift, and metamorphism recorded in ranges like the Cordillera Oriental (Colombia), Cordillera de la Costa (Venezuela), and the Patagonian Andes. Volcanic and plutonic records include calc-alkaline arcs, adakites, and high-K magmas linked to flat-slab subduction episodes documented across Peru, Bolivia, and Chile. Large ignimbrite provinces such as the Altiplano–Puna volcanic complex reflect continental magmatism coupled to crustal thickening and plateau formation.
South America hosts world-class mineral provinces: porphyry copper systems in Chile and Peru (e.g., Escondida, Chuquicamata), orogenic gold in Brazil and Guyana Shield (e.g., Morro do Ouro), iron deposits in the Quadrilátero Ferrífero of Minas Gerais, lithium brines across the Salar de Uyuni and Salar de Atacama, and massive sulfide and tin belts in the Bolivian Tin Belt. Hydrocarbon resources occur in the Vaca Muerta shale play, the Orinoco Belt heavy oil, and offshore fields in the Santos Basin and Gulf of Paria, driving exploration by companies and regulators such as Petrobras and national oil companies of Argentina and Venezuela.
The fossil record includes significant finds such as Notoungulata, Glyptodontidae, and Tyrannosauridae-era remains in Cretaceous–Cenozoic strata, and Mesozoic dinosaurs from the Ischigualasto Formation and La Colonia Formation. Paleobotanical assemblages from the Amazon and Patagonia document floral turnovers across the Paleogene and Neogene, while marine fossils in the Bahía Inglesa Formation and Pisco Formation preserve cetacean and avian evolution. Important institutions curating collections include the Museo Argentino de Ciencias Naturales, Museo Nacional de Historia Natural (Chile), and the Natural History Museum, London where South American specimens have informed global biogeographic and evolutionary syntheses.
Category:Geology by continent