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Gondwana (/ ɡ ɒ n d ˈ w ɑː n ə /) [1] was a large landmass, sometimes referred to as a supercontinent.The remnants of Gondwana make up around two-thirds of today's continental area, including South America, Africa, Antarctica, Australia, Zealandia, Arabia, and the Indian Subcontinent.
Wegener's continental drift hypotheses is a logical consequence of: the theory of thrusting (alpine geology), the isostasy, the continents forms resulting from the supercontinent Gondwana break up, the past and present-day life forms on both sides of the Gondwana continent margins, and the Permo-Carboniferous moraine deposits in South Gondwana.
The rocks comprising Patagonia occurred along the southwestern margin of the ancient supercontinent of Gondwana. During a period of continental rifting in the Cambrian period, a portion of Patagonia was separated from Gondwana, and the resulting passive margin that formed was a site of extensive sedimentation throughout the early-middle ...
The Gondwana supercontinent began to break up in the Middle Jurassic, about 167 million years ago. At that time, East Gondwana, comprising Antarctica, Madagascar, India, and Australia, began to separate from Africa. East Gondwana then began to separate about 115–120 million years ago when India began to move northward. [5]
About 182 million years ago the southern African portion of Gondwana passed over the Bouvet hotspot [21] [22] causing the crust under the Karoo Supergroup to rupture, releasing huge volumes of basaltic lava over the Clarens desert, covering nearly the whole of Southern Africa and other portions of Gondwana.The pile of lava that accumulated over ...
The initiation of Gondwana breakup, and transform faulting along the Davie Fracture Zone, occurred in the Toarcian (about 182 million years ago) following the eruption of the Bouvet (Karoo) mantle plume. At this time East Gondwana, comprising the Antarctic, Madagascar, Indian, and Australian plates, began to separate from the African plate.
[1] [3] These sediments deposited as result of a regional marine transgression swept over the Horn of Africa during the initial break-up of Gondwana. Resultant rocks include sandstone, limestone, shale, marls and evaporites (Adigrat Sandstone, Antalo Limestone, Amba Aradam Formation). [1]
The assembly and break-up of Gondwana are, in terms of the Earth's and South Africa's geological history, relatively recent events. Klein Swartberg Range, seen from the Laingsburg area Folded rock formations of the Swartberg Southern Gondwana during the Cambrian-Ordovician Periods. Today's continents into which this Supercontinent eventually ...