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14-422: The Bruce Spur is divided into two distinct segments separated by The north-west trending Bruce Canyon. The eastern rise reach up to 1,500 m (4,900 ft) below sea level and is bounded by steep slopes to the east and north. The western rise reaches 2,000 km (1,200 mi) and is bounded by more gently dipping slopes. The western rise probably formed during the rifting between India and Australia during

28-753: A single continental terrain. The Mawson Continent seems to have formed during the Kimban orogeny of around 1730–1690 Ma when the Gawler–Adélie Craton combined with the crust of the Miller Range of the Transantarctic Mountains . Later, around 1600–1550 Ma, the Coompana Block and its Antarctic extension was joined to the continent. The extent of the Mawson Continent is uncertain since Australia

42-623: A single terrain from the Archean until rifting in the Cretaceous . There are correlatable timelines between the Gawler–Adélie Craton, Curnamona Province and North Australian Craton around 2500–2430 Ma, 2000 Ma, 1865–1850 Ma, 1730–1690 Ma and 1600–1550 Ma. It is therefore plausible that throughout the Paleoproterozoic the Gawler– Adélie Craton and North Australian Craton were joined into

56-556: Is a stub . You can help Misplaced Pages by expanding it . Naturaliste Plateau The Naturaliste Plateau is one of several large submarine plateaus extending from Western Australia into the Indian Ocean . It is a rectilinear plateau that covers an area of 90,000 square kilometres. Its width is about 400 kilometres (250 mi) east-west and 250 km (160 mi) north-south. The water depths are from 1500 to 5000 metres. The Mentelle Basin and Naturaliste Trough lie between

70-459: Is now widely covered by Neoproterozoic to Phanerozoic rocks and Antarctica is almost entirely covered by ice and snow. The Gawler craton, Terre Adélie craton, Miller Range and Shackleton Range have few tectono-thermal events in common, apart from tectonism around 1700 Ma. Airborne and satellite magnetic geophysical data suggest that the Gawler-Adélie cratons differ in fundamental ways from

84-664: The Naturaliste Plateau and Gulden Draak rifted from the western Bruce Spur about 127 Ma. Continental rifting continued between the Bruce Spur and the Naturaliste Plateau for some 45 Ma after India broke off together with the two knolls. This rifting ended with onset of seafloor spreading between Australia and Antarctica around 83 Ma. 63°30′S 101°15′E  /  63.500°S 101.250°E  / -63.500; 101.250 This Wilkes Land location article

98-647: The Early Cretaceous, while the eastern rise probably formed during the break-up between Australia and Antarctica in the Late Cretaceous. The western part of the Bruce Spur was conjugate to Gulden Draak Knoll , now located on the western margins of the Perth Abyssal Plain , before the break-up between India, Australia, and Antarctica. Greater India and the Batavia Knoll (north of Gulden Draak) rifted from

112-712: The Miller Range and other parts of the East Antarctic Shield . There is evidence that suggests that the Miller Range terrain was accreted to the Gawler–Adélie Craton during the 1730–1690 Ma Kimban–Nimrod Orogeny, with a suture zone that may be at or near the location of the Nimrod Group . Australia and Antarctica separated between 85 Ma and 30 Ma. Tectonics in the Southern Terrane of the Shackleton Range during

126-764: The Naturaliste Plateau was flanked by what would become two microcontinents : the Batavia and Gulden Draak Knolls, which are now located on the western margin of the Perth Abyssal Plain 1,600 km (990 mi) from Australia. South of the plateau, during some 45 Ma after India and the two knolls broke off, rifting occurred between the plateau and the Bruce Rise , now located off Antarctica. This rifting continued until sea-floor spreading began 83 Ma. Continental metamorphic and granitic basement rocks have been dredged from both knolls. Protolith granite from Gulden Draak

140-650: The mainland and this plateau. The plateau is bordered by the Perth Abyssal Plain in the north and west and the Australian–Antarctic Basin in the south. It is located within the Australian marine park known as the South-west Corner Marine Park . The Naturaliste Plateau formed during the Early Cretaceous 136 Ma when Australia and India broke up and during the Late Cretaceous 83 Ma when Australia and Antarctica broke up. Lavas and intrusive rocks on

154-580: The other three flanks are relatively steep. The southern flank formed during the Australia-Antarctica break-up, the other flanks during the rifting between India and Australia. The continent ocean transition (COT) is 30–90 km (19–56 mi) wide on the north side and 250 km (160 mi) on the southern side where the plateau is flanked by the Diamantina Fracture Zone . Before India broke off from Australia-Antarctica at 127 Ma,

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168-408: The plateau flanks have ages of between 132-128 Ma. The volcanic sequence that consists of alternating basaltic flows and volcaniclastic beds, cut by multiple dikes, was recovered at IODP Site U1513 on the eastern flank. After the volcanic eruption, the Naturaliste Plateau subsided from shelf to bathyal depths during the Early Cretaceous. The eastern flank of the plateau slopes relatively gently, while

182-520: Was a continent that may have formed around about 1730 Ma (1,730 million years ago). It included the Gawler Craton of southern Australia and correlated terrains in Antarctica . Since very little of the historical continent is exposed, the full extent is conjectural. The Gawler craton and Terre Adélie craton share late Archean and early Proterozoic tectono-thermal events, and may be considered to be

196-769: Was emplaced in either the Australian Yilgarn Craton or the Antarctic Mawson Craton 2850 Ma. The Mesoproterozoic crust from this knoll is coeval with crust from the Naturaliste Plateau. Neoproterozoic - Cambrian (540–530 Ma) granite gneisses from the Batavia Knoll were emplaced during or after the formation of the Kuunga Orogen . 34°06′S 111°18′E  /  34.1°S 111.3°E  / -34.1; 111.3 Mawson Craton The Mawson Continent (or Mawson Block , Mawson Craton )

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