Physiographic Regions

Physiographic Regions ofSouth America

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

Eastern Highlands(cores of Gondwana shield)

• Brazilian Highlands

• Guiana Highlands

• Patagonian Highlands

Striking similarity to geology and fauna in shields in Africa, Australia,India

340-280 mya: ice sheet S. America,Africa, Madagascar

Divisions of Brazilian Highlands:uplands (2000-3000 ft)

1.Brazilian Highlands

2.Sertão– Paraná Plateau

3.Mato Grosso plateau– Pantanál

4.Serro do Mar (Great Escarpment)

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

SERRO DO MAR

SERTÃO

MATOGROSSO PLATEAU

PARANÁPLATEAU

Brazilian Highlands

Mineral resources: iron ore, diamonds, gold, manganese, tungsten

Sertão

• semiarid

• eroded

Paraná Plateaulava plateau; more humid

Iguaçu River flows over edge of plateau

capivara

Mato Grosso Plateau

• Upland, rolling hills, mountains, plateaus

• Tributaries of Amazon

• Industrial ores

• Western frontier (Brasilia)

Brasilia

Pantanálwithin more humid part of Mato Grosso

region; wetlands

Pantanál

Serro do MarGreat Escarpment (up to 9000 ft)

Cities on narrow coastal plain

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

Guiana Highlands

Guiana Highlands

• Mining

• Agriculture along northern coastal plain

• Some erosional remnants remain– Tepuis: flat-topped mountains

• Average elevation: 4500 ft.

• Some is inaccessible and rugged– Angel Falls (3200 ft. over edge of tepuy)

• World’s highest waterfall

Angel Falls

Guianan Cock-of-the-Rock

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

Patagonian Plateau

Patagonian Plateau

• Semiarid

• Series of plateaus that get progressively higher (reaching 5000 ft. until Patagonian Andes)

Patagonia

Lake Argentino

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

Central Lowlands

Underlain by marine deposits; from a time when shallow seas extended between Guiana and Brazilian Highlands, before Andes emerged

–Much of the lowland region is flooded during rainy season

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

EASTERN HIGHLANDS

Llanos

Amazon basin

Pampas

Gran Chaco

Llanos• Northern Llanos: flat plains of the Orinoco River• High Llanos: east of Andean foothills

– Good soils, agriculture

• Low Llanos: savannas; cowboys & cowgirls

Orinoco River

Gran Chaco

• Argentina, Bolivia, Paraguay, Brazil

• Lowland alluvial plain• Arid• Cattle ranching• Cotton, peanuts,

meat, hides

Pampas• Temperate grassland

plain• From southernmost

Brazil, across Uruguay, to Colorado River in Argentina

• Fertile soils• cattle, sheep (gauchos)• Grain, flax, soy,

sunflowers, vegetables

Part of La Plata – Parana Basin

Ombu

Amazon basin(wetlands and Amazon floodplain)

Amazon

• ¾ size US• Greatest reserve of

biodiversity• 170 Indian cultural groups• Largest continuous

stretch of tropical rain forest

• Greatest carbon sink on earth

• 20% world’s available fresh water

EASTERNHIGHLANDS

EASTERN HIGHLANDS

WESTERNALPINE SYSTEM

CENTRAL LOWLANDS

EASTERN HIGHLANDS

EASTERNHIGHLANDS

EASTERN HIGHLANDS

CENTRAL LOWLANDS

EASTERN HIGHLANDS

Andes

Altiplano

Atacama Desert

CentralValley of Chile

Andes

subduction

Central Range Andes, Colombia

Andes in Patagonia

Andes

Altiplano

• Intermontane plateau between eastern and western ranges of Andes

• In Bolivia and Peru

• averages 12000 ft.

• Lake Titicaca is northern limit

• La Paz

• salares

llareta

Atacama Desert

• 2000 miles long

• Driest place on earth– Rains once every ten years

• Collect water from fog

Fog collectors

Central Valley, Chile

• Highly urbanized

• Rich in nitrates and copper

• Irrigated commercial agriculture– For Northern markets

Physiographic Regions ofMexico, Central America and

Caribbean

Neovolcanic Range

Southern Highlands

Eastern Sierra Madre

Western Sierra MadreMesa del Norte

Mesa Central

Neovolcanic Axis

• In Mexico• Series of volcanoes• Subduction of Cocos

plate beneath North American

Neovolcanic Axis

• In Mexico• Series of volcanoes• Subduction of Cocos

plate beneath North American

Central American volcanic axis

• parallels Pacific coast from Panama to Chiapas

• Cocos plate subducts beneath Caribbean plate

Central American volcanic axis

• parallels Pacific coast from Panama to Chiapas

• Cocos plate subducts beneath Caribbean plate

• Volcanoes (7000 – 12000 ft)

Interior highland region of Central America consists of ash-filled valleys.

Caribbean

• Summits of a submerged mountain chain, continued in mountains of Honduras

2 volcanic arcs

Lesser Antilles

• Two volcanic arcs :1. Outer Arc (older):

• Anguilla• St. Martin• St. Barthélemy• Barbuda• Antigua• Marie Galante• Eastern Guadelope• Barbados (part) Arid; mineral poor;Not volcanically active

Lesser Antilles

• Two volcanic arcs :2. Inner Arc

(younger):• All the rest!

Volcanically active; fertile soil; abundant rainfall