Relief in Africa and the World

Lessons

Senior 3 · Geography

Relief in Africa and the World

4 lessons

Lesson 3 of 4

Major Relief Forms of the Other Continents

25 min

Let's begin

Africa's highest peaks stand alone: Kilimanjaro rises as a single volcano from the plateau. Look at a relief map of the Americas or Asia and you see something different: mountains that run in long, unbroken lines for thousands of kilometres, like the Andes along the whole west coast of South America. Why the difference? This lesson surveys the relief of the other continents and finds the pattern behind it.

Definition

Young fold mountains: high, steep, jagged mountain chains formed by folding in the last 100 million years or so, where tectonic plates collide, e.g. the Himalayas, the Alps, the Andes and the Rockies.

Old fold mountains: much older folded ranges that erosion has worn down into lower, rounded mountains, e.g. the Appalachians and the Urals.

Shield: a very old, stable block of hard rock forming a low plateau at the core of a continent, e.g. the Canadian Shield.

Figure 7. The main relief features of the other continents. Drawn by Ganzaa from Natural Earth data.

Continent by continent

Continent	Main relief forms
Europe	Mountains: Alps and Pyrenees (young fold); Scandinavian Mountains and Urals (old); the Urals mark the boundary with Asia. Plateaus: Meseta of Spain. Plains: The North European Plain, from France to Russia.
Asia	Mountains: Himalayas, with Mount Everest (8,849 m), the world's highest mountain (young fold). Plateaus: Tibetan Plateau (average height over 4,500 m, the highest large plateau); Deccan Plateau of India. Plains: West Siberian Plain; Indo-Gangetic Plain; plains of eastern China.
North America	Mountains: Rocky Mountains and the other western ranges (young fold); Appalachians (old); Denali (6,190 m) in Alaska. Plateaus: Canadian Shield; Colorado Plateau. Plains: Great Plains and Central Lowlands; Atlantic and Gulf coastal plains.
South America	Mountains: Andes, about 7,000 km long, the longest mountain range on any continent (young fold, with volcanoes); Aconcagua (6,961 m). Plateaus: Brazilian Highlands; Guiana Highlands; Patagonia. Plains: Amazon Basin; Pampas; Llanos.
Oceania	Mountains: Great Dividing Range of eastern Australia (old); Southern Alps of New Zealand (young fold); New Guinea Highlands. Plateaus: Western Plateau, covering most of Australia. Plains: Central Lowlands of Australia.
Antarctica	Mountains: Transantarctic Mountains; Vinson Massif (4,892 m). Almost all the land is buried under an ice sheet.

The Himalayas photographed from the International Space Station: row after row of steep, snow-capped ridges, typical of young fold mountains. Photo: NASA, public domain, via Wikimedia Commons.

Highest and lowest points

Figure 8. The highest point of each continent. Drawn by Ganzaa.

Continent	Lowest point	Height (m)
Asia	Shore of the Dead Sea	about −430 (it is falling as the sea shrinks)
Africa	Lake Assal, Djibouti	−155
South America	Laguna del Carbón, Argentina	−105
North America	Badwater Basin, Death Valley, USA	−85
Europe	Caspian Sea shore	−28
Oceania	Lake Eyre (Kati Thanda), Australia	−15

The pattern: why mountains lie where they do

Young fold mountains form belts along plate boundaries. One belt circles the Pacific: the Rockies and the Andes. Another, the Alpine–Himalayan belt, runs from the Atlas and the Alps through the Himalayas. These are the highest, steepest ranges, and many have volcanoes and earthquakes.
Old mountains lie inside plates. The Appalachians, the Urals and the Great Dividing Range were folded long ago, far from today's plate edges, and have been worn low.
Continental cores are shields and plateaus: the Canadian Shield, the Brazilian Highlands, the Western Plateau of Australia and most of Africa.
Great plains and basins lie between the mountains and the shields, built of sediment carried by great rivers: the Amazon, the Mississippi, the Ganges.

Africa is the exception among the large continents: apart from the Atlas in the far north-west, it has no young fold mountains, because most of it lies inside one plate. Its high relief comes instead from uplift, rifting and volcanoes.

GEO GIRL, a geologist: the story of how the collision of the Indian and Eurasian plates built the Himalayas and the Tibetan Plateau. Listen for why the rocks were folded and pushed up so high.

Worked example

Worked example 1: comparing two continents. Compare the relief of South America with the relief of Africa.

Similarities: both have old plateaus in the east (Brazilian Highlands; East and Southern African plateaus) and a huge, low, forested river basin near the Equator (Amazon; Congo).

Differences: South America has a continuous chain of young fold mountains, the Andes, along its whole western edge, and its highest point (Aconcagua, 6,961 m) is a fold-mountain peak. Africa has no such chain; its highest point (Kilimanjaro, 5,895 m) is a volcano, and its most striking feature is the rift valley.

Worked example

Worked example 2: using the figures. How much higher is Mount Everest than Kilimanjaro, and what percentage of Everest's height does Kilimanjaro reach?

Difference: $8849 - 5895 = 2954\,\text{m}$ .
Percentage: $\frac{5895}{8849} \times 100 \approx 66.6\%$ .

Answer: Everest is 2,954 m higher; Kilimanjaro reaches about two thirds of Everest's height.

Warning

Europe's highest point depends on where you draw the boundary. If the Caucasus is counted in Europe, the highest point is Mount Elbrus (5,642 m); if not, it is Mont Blanc in the Alps (about 4,800 m). State which you mean. Heights of famous peaks also change a little with new surveys; Everest's 8,849 m comes from a survey of 2020.

Tip

One chain, two belts. Remember the two great belts of young fold mountains: the Pacific belt (Rockies, Andes) and the Alpine–Himalayan belt (Atlas, Alps, Himalayas). Almost every young fold range in the exam lies on one of them.

Practice

Name the highest mountain on each of Asia, South America and North America, with its height.
Name two young fold mountain ranges and two old fold mountain ranges, giving the continent of each.
Which mountain range forms part of the boundary between Europe and Asia?
Name one plateau and one plain in (a) North America, (b) Asia.
How many metres higher is Aconcagua than Kilimanjaro?
Describe the main difference between young and old fold mountains, and explain it.
"Africa is a continent of plateaus, while South America and Asia are continents of great mountain chains." Assess this statement using evidence from this unit.

Show answersHide answers

Asia: Mount Everest, 8,849 m. South America: Aconcagua, 6,961 m. North America: Denali, 6,190 m.
Young: e.g. the Himalayas (Asia), the Alps (Europe), the Andes (South America), the Rockies (North America). Old: e.g. the Appalachians (North America), the Urals (Europe and Asia), the Great Dividing Range (Australia), the Scandinavian Mountains (Europe).
The Ural Mountains.
(a) Plateau: the Canadian Shield or the Colorado Plateau; plain: the Great Plains. (b) Plateau: the Tibetan Plateau or the Deccan; plain: the West Siberian Plain or the Indo-Gangetic Plain.
$6961 - 5895 = 1066\,\text{m}$ .
Young fold mountains are high, steep and jagged; old ones are lower and rounded. Old mountains have been exposed to weathering and erosion for hundreds of millions of years, while young ones are still being raised at active plate boundaries.
Largely true: most of Africa is plateau, its highest peaks are single volcanoes and it has no long young fold chain except the Atlas; South America has the Andes and Asia the Himalayas. But it is not the whole picture: South America and Asia also have huge plateaus (Brazilian Highlands, Tibetan Plateau, Deccan) and great plains, and Africa has high mountains too (Kilimanjaro, Rwenzori). A fair answer agrees with the main idea and gives these qualifications.

Sources and credits

List of elevation extremes by region, Mount Everest, Andes, Tibetan Plateau and Fold mountains: Wikipedia contributors, Wikipedia, CC BY-SA 4.0, adapted by Ganzaa.
Map: Large World Topo Map 2, MTBlack, Wikimedia Commons, CC BY-SA 4.0.
Photo: Himalayas from ISS, NASA, Wikimedia Commons, public domain.
Figure 7 outline: Natural Earth, public domain.

Video: The Himalayas: The Geological Story of Earth's Greatest Mountain Collision, GEO GIRL, embedded from YouTube.

Figures 7 and 8, the worked examples and the practice exercises are written by Ganzaa.

This lesson adapts CC BY-SA material and is shared under CC BY-SA 4.0.

1Continent by continent

2Highest and lowest points

3The pattern: why mountains lie where they do

Continent by continent

Highest and lowest points

The pattern: why mountains lie where they do