Which other rock types are found underneath the Karoo Supergroup?
(A) Horizontally bedded conglomerate, red sandstone and siltstone are attributed to the Karoo Supergroup.
What is a supergroup in geology?
A supergroup is a set of two or more associated groups and/or formations that share certain lithological characteristics. A supergroup may be made up of different groups in different geographical areas.
How is the Karoo landscape formed?
The Karoo Supergroup was formed in a vast inland basin starting 320 million years ago, at a time when that part of Gondwana which would eventually become Africa, lay over the South Pole. As Gondwana drifted northwards, the basin turned into an inland sea with extensive swampy deltas along its northern shores.
Which unit of the Karoo Supergroup is composed of flood basalts?
The Drakensberg Group comprises minor sedimentary (ie. sandstones, lapilli deposits, pyroclastic deposits, and igneous (ie. continental flood basalt/andesite sequences, shallow intrusive dikes and sills, and diatremes) and is part of the greater volcanic extrusive rock sequences of the Karoo Igneous Province.
How was the Karoo Supergroup formed?
The Karoo Supergroup is the most widespread stratigraphic unit in Africa south of the Kalahari Desert. This basin was formed by the subduction and orogenesis along the southern border of what eventually became Southern Africa, in southern Gondwana.
What does group mean in geology?
A group is a lithostratigraphic unit, a part of the geologic record preserved in rock strata. Groups are generally divided into individual formations. Groups may sometimes be combined into supergroups.
Where is Lowveld in South Africa?
Mpumalanga province
The Lowveld is situated in the Mpumalanga province of South Africa. Mpumalanga means ‘place where the sun rises’ and this is well suited, as Mpumalanga is South Africa’s eastern most province. Nelspruit is the provincial capital and it serves as a gateway to the Lowveld.
How big is the Karoo in South Africa?
about 153,000 square miles
Altogether the Karoo occupies about 153,000 square miles (395,000 square km), about one-third of the total area of South Africa.
Which plateau is in South Africa?
Great Karoo, Karoo also spelled Karroo, Afrikaans Groot Karoo, also called Central Karoo, plateau basin in Western Cape province, South Africa, lying between the Great Escarpment (north) and the Swartberg (south).
What are the economic aspects of South Africa’s geology?
Mineral wealth Overall, the country is estimated to have the world’s fifth-largest mining sector in terms of GDP value. It has the world’s largest reserves of manganese and platinum group metals (PGMs), according to the US Geological Survey, and among the largest reserves of gold, diamonds, chromite ore and vanadium.
What are the examples of geologic formations?
Examples of these geological formations which form aquifers include sandstone, conglomerate, fractured limestone, and unconsolidated sand and gravel formations. Another example of an aquifer system is a fractured volcanic rock formation such as columnar basalt.
When did the Karoo Supergroup form?
The latter has been deposited during the Archaean period (between 3100 and 2000 million years ago) with the Karoo Supergroup being deposited on top during the Phanerozoic period (60 million years ago) ( McCarthy and Rubidge, 2005 ).
Where are the oldest rocks in the Karoo?
However, the entire suite in this region slopes downwards towards the north and east, so that the oldest rocks are exposed in the south and west, while the youngest members of the Supergroup are exposed in the north, where the entire Cape Supergroup dives beneath the Karoo rocks.
How did the Karoo Supergroup change the lithologic character of sedimentary rocks?
Tectonic and climatic shifts from the southern to the northern margins of the basin during the deposition of the Karoo Supergroup altered the lithologic character of the rocks in both space and time.
What is the Ecca Group of the Karoo?
These sedimentary deposits are termed the Ecca Group of the Karoo Supergroup. They consist largely of shales and sandstones, and extend over the entire former Karoo Sea, but the southerly deposits do not contain coal, even though rivers from the Cape Fold Mountains formed small deltas.
