Search results
Results from the WOW.Com Content Network
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 supercontinent Pangaea was rifting during the Triassic—especially late in the period—but had not yet separated. The first nonmarine sediments in the rift that marks the initial break-up of Pangea—which separated New Jersey from Morocco—are of Late Triassic age; in the U.S., these thick sediments comprise the Newark Supergroup. [44]
A supercontinent cycle is the break-up of one supercontinent and the development of another, which takes place on a global scale. [4] Supercontinent cycles are not the same as the Wilson cycle, which is the opening and closing of an individual oceanic basin. The Wilson cycle rarely synchronizes with the timing of a supercontinent cycle. [1]
The second major phase in the break-up of Pangaea began in the Early Cretaceous (150–140 Ma), when Gondwana separated into multiple continents (Africa, South America, India, Antarctica, and Australia). The subduction at Tethyan Trench probably caused Africa, India and Australia to move northward, causing the opening of a "South Indian Ocean".
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 ...
During the early breakup of Gondwana and associated continental rifting, the Patagonian landmass underwent large-scale rotations. Paleomagnetic data from late Jurassic-early Cretaceous rocks in the southern portion of the North Patagonian Massif indicate that clockwise rotation of up to 30 degrees occurred in that area during the Early ...
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.