Andean foreland basins


The Andean foreland basins or Sub-Andean basins are a group of foreland basins located in the western half of South America immediately east of the Andes mountains. The Andean foreland basins in the Amazon River's catchment area are known as the Amazonian foreland basins.
In part sediment accumulation, uplift and subsidence of the Andean foreland basins is controlled by transverse zones of "structural accommodation", likely corresponding to ancient continent-wide faults. From the Bolivian Orocline north these zones of accommodation runs with a NEE-SWW orientation and south of the orocline they run with a NW-SE orientation. The Andean foreland basins in Bolivia have largely accumulated continental sediments, most of them of clastic nature.
Beginning in 1920 the Ecuadorian and Peruvian basins were explored for petroleum and in the 1970s their hydrocarbon production increased greatly.
NameLatitudeCountryDetails
Cesar-Ranchería Basin11–8° NColombiaIntermontane foreland basin enclosed by the Sierra Nevada de Santa Marta in the northwest, the Oca Fault in the north, the Serranía del Perijá in the east to southeast and the Bucaramanga-Santa Marta Fault in the west.
Eastern Venezuela Basin10–8° NVenezuelaThe Eastern Venezuela Basin lies between several geological structures. To the south it bounds Guiana Shield, to the north metamorphic rocks of the easternmost Andes, to the west the Espino Graben, to the northeast the Barbados accretionary complex and to the east it bounds to the oceanic crust of the Atlantic Ocean.
Barinas Basin10–7° NVenezuela
Middle Magdalena Valley8–4° NColombiaIntermontane foreland basin enclosed by the Bucaramanga-Santa Marta Fault in the northeast, the Eastern Ranges in the east, the Girardot High in the south and the Central Ranges in the west.
Llanos Basin7–3° NColombiaMost prolific hydrocarbon producing basin of Colombia, enclosed by the Venezuelan border in the north, the Guiana Shield in the east, the Guaviare River in the south and the foothills of the Eastern Ranges in the west.
Upper Magdalena Valley4–1° NColombiaIntermontane foreland basin enclosed by the Girardot High in the north, the Eastern Ranges in the east, and the Central Ranges in the west.
Caguán-Putumayo Basin3–0° NColombiaEnclosed by the Vaupés High in the north, the Peruvian and Ecuadorian borders in the south and the Eastern and Central Ranges in the west.
Oriente Basin3° N–11° SEcuadorThe Oriente Basin owes its configuration to the tectonic inversion of rifts of Triassic-Jurassic age due to the tectonic conditions of transpression that have prevailed in the region since the Late Cretaceous.
Marañón Basin2–6° SPeru
Ucayali Basin6–12° SPeru
Madre de Dios Basin10–13° SBrazil, Bolivia, Peru
Beni Plain Basin13–17° SBolivia
Santa Cruz Basin17–23° SArgentina, Bolivia, Brazil, Paraguay
Northwest Basin22–32° SArgentina, Brazil, Paraguay
Cuyo Basin27–37° SArgentinaThe Cuyo Basin is an elongated sedimentary basin of NNW-SSE orientation limited to the west by the Sierra Pintada System and to the east by the Pampean pericraton. To the north the basin reaches the area around the city of Mendoza. The basin existed already during the Triassic but its current shape is derivative of the Andean orogeny.
Neuquén Basin34–40° SArgentina, ChileNeuquén Basin is a sedimentary basin that originated in the Jurassic and developed through alternating continental and marine conditions well into the Tertiary. The basin bounds to the west with the Andean Volcanic Belt, to the southeast with the North Patagonian Massif and to the northeast with the Sierra Pintada System.
Magallanes Basin
48–54° SArgentina, ChileThe Magallanes Basin is a foreland basin located in southern Patagonia. The basin covers a surface of about 170.000–200.000 km2 and has a NNW-SSE oriented shape. The basin evolved from being an extensional back-arc basin in the Mesozoic to being a compressional foreland basin in the Cenozoic.