Gondwana

Gondwana (/ɡɒnˈdwɑːnə/ gond-WAHN-ə; Sanskrit: [goːɳɖɐʋɐnɐ]) 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.

Gondwana was formed by the accretion of several cratons (large stable blocks of the Earth's crust), beginning c. 800 to 650 Ma with the East African Orogeny, the collision of India and Madagascar with East Africa, and culminating in c. 600 to 530 Ma with the overlapping Brasiliano and Kuunga orogenies, the collision of South America with Africa, and the addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Paleozoic Era, covering an area of some 100,000,000 km² (39,000,000 sq mi), about one-fifth of the Earth's surface. It fused with Laurasia during the Carboniferous to form Pangaea.

Gondwana began to separate from northern Pangea (Laurasia) during the Triassic, and started to fragment during the Early Jurassic (around 180 million years ago). The final stages of break-up saw the fragmentation of the Antarctic land bridge (involving the separation of Antarctica from South America and Australia, forming the Drake and Tasmanian Passages), which occurred during the Paleogene (from around 66 to 23 million years ago (Ma)). Gondwana was not considered a supercontinent by the earliest definition, since the landmasses of Baltica, Laurentia, and Siberia were separated from it. To differentiate it from the Indian region of the same name (see § Name), it is also commonly called Gondwanaland.

Regions that were part of Gondwana shared floral and faunal elements that persist to the present day.

The continent of Gondwana was named by the Austrian scientist Eduard Suess after the Indian region of the same name, which is derived from Sanskrit गोण्डवन goṇḍavana ('forest of the Gonds'). The name had been previously used in a geological context, first by H. B. Medlicott in 1872, from which the Gondwana sedimentary sequences (Permian-Triassic) are also described.^{[citation needed]}

Some scientists prefer the term "Gondwanaland" for the supercontinent to make a clear distinction between the region and the supercontinent.

The assembly of Gondwana was a protracted process during the Neoproterozoic and Paleozoic, which remains incompletely understood because of the lack of paleo-magnetic data. Several orogenies, collectively known as the Pan-African orogeny, caused the continental fragments of a much older supercontinent, Rodinia, to amalgamate. One of those orogenic belts, the Mozambique Belt, formed 800 to 650 Ma and was originally interpreted as the suture between East (India, Madagascar, Antarctica, Australia) and West Gondwana (Africa and South America). Three orogenies were recognised during the 1990s as a result of data sets compiled on behalf of oil and mining companies: the East African Orogeny (650 to 800 Ma) and Kuunga orogeny (including the Malagasy orogeny in southern Madagascar) (550 Ma), the collision between East Gondwana and East Africa in two steps, and the Brasiliano orogeny (660 to 530 Ma), the successive collision between South American and African cratons.

The last stages of Gondwanan assembly overlapped with the opening of the Iapetus Ocean between Laurentia and western Gondwana. During this interval, the Cambrian explosion occurred. Laurentia was docked against the western shores of a united Gondwana for a brief period near the Precambrian and Cambrian boundary, forming the short-lived and still disputed supercontinent Pannotia.