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With the aid of diagrams, describe the appearance and mode of formation of any two of ...

With the aid of diagrams, describe the appearance and mode of formation of any two of the following landforms: \
(a) Delta; (b) block mountain; (c) rock pedestal.
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
    Correct Answer: Option n
    Explanation:



    (a) DELTA
    Appearance
    — Fan - shaped
    — Found usually in the mouth rivers
    — Characterized by distributaries
    — Birds foot, e.g Missisippi delta
    — Estuarine de e.g Vistula
    — Arcuate Delta, e.g Niger delta
    — Cuspate type, e.g Ebro of Spain.
    Mode of Formation
    — Formed by the deposition of loads carried from th upper part of the river.
    — Deposition takes place at the mouth of the river.
    — Absence of strong current leads to the blocking c the flow of the river.
    — Causing division of the main river into several distributaries.
    — The distributaries extend into the sea to form a sheltered coast with shallow water.
    — River flows through the distributaries into the sea
    Appearance
    — Usually flat topped
    — Steep sided
    — Could be tilted
    — Associated with faults
    — Associated with rift valleys
    — Examples:- Vosges, Black Forest, Ruwenzori.
    Formation
    — Results from lateral or vertical earth movements
    — Causing faulting.
    — Faulting may result from tensional / compressional forces.
    — Tensional Forces pull crystal blocks apart
    — Leaving the middle block to form block mountain
    — Compressional forces push the outside blocks up to form block mountains.
    Appearance
    — Consists of horizontal layers of hard and soft rocks Like a pillar in structure
    — Narrow at the base and broader at the top
    — May range from 10 -15 metres high
    — Flat / dome - shaped
    — Irregular surface.
    Formation
    — Alternate bands of soft and hard horizontal rocks lying at right angles to the prevailing wind.
    — Formed by wind abrasion
    — Abrasive action attacks alternate horizontal layers of hard and soft rocks.
    — Soft rocks are removed (eroded) faster than the hard rocks.
    — Abrasion is stronger at ground level, resulting in serious under-cutting.
    — Irregular-shaped feature called rock pedestal is produced.
    — Found in deserts e.g Sahara Desert.

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