Fissure eruptions at Mt Nyiragongo. Image credit Imgsoup.

Fissure eruptions at Mt Nyiragongo. Image credit Imgsoup.

ZIMSEC O Level Geography Notes: 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.

To access more topics go to the Geography Notes page.

- See latest Zimbabwe grocery prices -

Deals

SEE LATEST SUPERMARKET PRICES, SHOP FOR GROCERIES VIA WHATSAPP
SEE PRICES & NEWS
We publish the latest grocery prices from Zimbabwean supermarkets. We also deliver groceries online