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Fold Mountains
Fold Mountains are found near the edges of continents.
They were formed as a result of folding.
This happened when two forces moving against each other made the young sedimentary rocks to fold upwards.
The rocks that were very old would break
The lifted parts are called anticlines and sunken parts are called synclines Forces that caused folding were compressional forces.
Examples of Fold Mountains in Africa:
- Atlas mountains in Morocco
- Cape ranges in South Africa
Volcanic Mountains
Volcanic mountains were formed when molten rocks known as magma forced their way on the surface of the earth.
They were formed as a result of volcanic activities. A Vent is an opening / a feature through which hot molten rocks, water, steam or ash passes to reach the earth’s surface.
Magma are molten rocks found under the surface of the earth.
Lava is the solidified magma that has cooled and it is found on the earth’s surface. Crater is a depression on a volcanic mountain.
Lava may flow over a large area forming plateaus or cones(domes).
Diagram showing volcanic mountain
Types of volcanic mountains.
- Active volcanoes.
- Dormant volcanoes.
- Extinct volcanoes.
Active volcanoes:
These are volcanoes that erupt frequently.
Dormant/sleepy volcanoes:
These are volcanoes that are sleeping but are likely to erupt later.
Extinct/dead volcanoes:
These are volcanoes that are old and will not erupt again.
Examples of volcanoes in Africa:
Block Mountains
Block mountains were formed by faulting.
These are formed when the block between faults is lifted up by forces coming from the centre of the earth.
The middle block is forced to sink.
The raised blocks are known as horst or block mountains.
Examples of Block Mountains in Africa
Diagram showing the formation of Block Mountains
Map of Africa showing mountains and highlands
Basin
This is a large low lying land found with in the earth’s surface.
It can be between a plateau and a plateau or a highland.
Africa has the basins below;
- Congo basin
- Chad basin
- Okavango basin
- Niger basin
- Nile basin
- Orange basin
- Limpopo basin
- Victoria basin
- Zambezi basin
Human activities in basins
- Farming
- sand mining
- Fishing
- Brick making
- Tourism