8. Relief. Minerals.

Map Questions.

1.Where do lowlands cover a larger area, in North or South America?

2What large lowland is there in South America?

3.What lofty mountain system extends along the Pacific coast?

Relief. In relief South America is very much like North America. In both we find: (1) lofty chains of young mountains in the west, along the Pacific coast; (2) ancient mountains and plateaus in the east; (3) central lowlands in between, along the rivers. As compared to North America, South America is less elevated. Vast regions are occupied by lowlands.

In the centre of South America, close to the Equator, lie the Amazon Lowlands, the largest in the world. They are covered with sea deposits and river silt. To the north lie the Orinoco Lowlands, to the south the La Plata Lowlands, extending in a northern to southern direction.

In the eastern part of the continent are the Brazilian H i g h 1 a n d s, composed of old rocks. They rise to the south-east and come to an abrupt end at the Atlantic. Further north are the Guiana Highlands.

Along the entire Pacific coast extend the Cordilleras, called the Andes in South America. The Andes consist of young mountains.

They are higher than the North American Cordilleras. Perennial snow covers their tops even on the Equator. Among the peaks are many extinct and active volcanoes. Between the ranges are lofty plateaus. In the south the Andes are continued through Tierra del Fuego.

There often occur earthquakes in the neighbourhood of the Andes. A very violent earthquake occurred in 1960 on the south coast of the Pacific. It caused landslides in the mountains. Some of the extinct volcanoes began ejecting smoke, ash and lava, and several new volcanoes appeared. The neighbourhood was greatly changed. New mountains, river sand lakes appeared, while some old ones vanished.

Great waves, called tsunamis, arose in the Pacific. Travelling at a rate of 700 kilometres an hour, they crossed the ocean and reached the shores of Asia. Ten-metre waves pounced on the east coast of Japan, flooding tens of thousands of houses, overturning hundreds of fishing-boats and drowning many people.

Minerals. South America is rich in many kinds of minerals, but pool' in coal. There are large deposits of oil in the north: along the coast of the Caribbean Sea and at the foot of the Andes. In the neighbourhood of the Andes there are rich deposits of copper, tin, zinc and lead. At the very shores of the Pacific there is saltpetre, used as a fertilizer. There are bauxites near the Atlantic coast. Rich deposits of iron ore and manganese are found in the Brazilian and Guiana Highlands (manganese is used in making cast iron and steel).

Questions and Assignments.

1.Study the map and determine the highest points of the Andes and Brazilian Highlands. Account for the frequency of earthquakes in the Andes.

2.Mark and name on the outline map the lowlands, mountains and highlands you have studied.

3.Use symbols to show on the outline map the mineral deposits of South America.