The Pampas, also called the Pampa, Spanish La Pampa, vast plains extending westward across central Argentina from the Atlantic coast to the Andean foothills, bounded by the Gran Chaco (north) and Patagonia (south). The name comes from a Quechua Indian word meaning “flat surface.” The Pampas have a gradual downward slope from northwest to southeast, from approximately 1,640 feet (500 metres) above sea level at Mendoza to 66 feet (20 metres) at Buenos Aires. Apart from a few sierras in the northwest and south, most of the region appears perfectly flat. Several smaller plains in other parts of South America, such as the desert of northern Chile, are also referred to by the term Pampas.
The Argentine Pampas covers an area of approximately 295,000 square miles (760,000 square km) and is divided into two distinct zones. The dry zone in the west, which includes most of La Pampa province, is largely barren, with great saline areas, brackish streams, and sandy deserts. The humid zone in the east, a much smaller area that includes part of Buenos Aires province, is temperate and well-watered and is the economic heart of the nation and the country’s most populated area. The soil consists chiefly of fine sand, clay, and silt washed down toward the Atlantic by the great rivers or blown in dust storms from the west. Cool winds from the south periodically meet warm air from the tropical north, creating violent gales accompanied by heavy rain in the neighbourhood of Buenos Aires. These storms are known as pamperos. Characteristic animals of the Pampas include foxes, skunks, small herds of guanaco, viscachas, bush dogs, and many bird species related to the sparrows, hawks, and waterfowl of the North American prairies.