Lava Plateaus

• Lava eruptions through narrow cracks (fissures) tends to be very quiet and subdued.
• The lava spreads out over the surrounding countryside.
• Successive lava outpourings causes successive layers of lava to build up.
• This may completely cover up the features of the surrounding region.
• Sometimes these layers of lava may be hundreds of meters thick
• The lava layers may accumulate in the depressions within the vicinity of the eruptions and rise to be high enough to bury the preexisting terrain.
• Resulting in high and fairly level features often that are referred to as lava plateaus.
• Some lava plateaus are very extensive in size and can cover thousands of kilometers for example the Haruj al Aswad (sometimes anglicized as Charudsch al-Aswad)   Plateau in Libya.
• Part of the Drankesberg Mountains in South Africa may be remnants of a lava plateau.
• At times due to subsequent erosion by rivers the original surfaces may be exposed on the floor of very deep valleys.
• Rivers crossing these plateaus often carve out deep gorges.
• These plateaus sometimes provide fertile soils.

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