(a) What is a plateau? (b) List two types of plateaux. (c) Describe the formation of any one type of plateau listed in (b) above. (d) Highlight three ways in which plateaux are of importance to man.
Explanation
(a) Definition of a plateau A plateau is an elevated upland with extensive level surface and usually descending steeply to the surrounding lowland (b) Types of Plateaux (a) Tectonic plateau. (b) Volcanic plateau or lava plateau. (c) Residual plateau or dissected plateau. (c)(i) Tectonic Plateau. Mode of formation.
It is formed as a result of earth movements resulting in folding or faulting. Folding and faulting causes uplift and depressic of some areas. The uplifted area of level land form tectonic plateau. Examples include Deccan plateau (India), Jos plates (Nigeria) Bolivian plateau (Andes - South America).
(ii) Volcanic Plateau / Lava Plateau.
It is formed by volcanic activity when there is crack or fissure, pressure is released. Magma is ejected onto the earth's surface. Lava accumulate and harden to form the plateau. Examples include Antrim plateau (Northern Ireland), Biu Plates (Northern Nigeria), Columbia Snake Plateau.
(iii) Residual Plateau
They originate from either tectonic or volcanic plateaux. Formed from ancient fold mountains which have been eroded ar weathered. It may also have been formed from highlands along whose edges rivers have carried out deep narrow vane), (dissected plateau). The high and extensive plateaux are gradually worn down. Examples include Middle Rhine plateau, Fouta Djallon highland. Jos and Enugu plateaux, Kumasi Plateau,.etc. They commonly look like series of ridges interspersed by plain land.
(d)Importance of Plateau to man (i) Some plateaux are rich in mineral e.g. iron-ore, copper, etc. (ii) Plateaux in tropical lands have cooler climate and favour settlement e.g. Jos Plateau. (iii) Some plateaux favour tourism especially those in the tropics. (iv) It serves as good grazing land for animals. (v) It encourages farming e.g. Deccan plateau is ideal for tea and jute cultivation. (vi) It serve as sources of rivers e.g. Fouta Djallon Highlands. (vii) Waterfalls at plateaux edges could serve as source of H.E.P.