Wallabi Limestone

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Wallabi Limestone is the name [1] given to the dense calcretised, limestone platform that underlies the Wallabi Group of the Houtman Abrolhos, an archipelago off the coast of Western Australia. This platform, which arises abruptly from a flat shelf, is about 40 metres thick, and is of marine biogenic origin, having originated as a coral reef. It reached its maximum size during the Eemian Stage (about 125,000 years ago), when sea levels were higher than at present. The subsequent fall in sea level resulted in the reef becoming emergent in places, thus forming the basement of the group's "central platform" islands, namely West Wallabi Island, East Wallabi Island and North Island. [2] [3]

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References

  1. "Wallabi Limestone". Australian Stratigraphic Names Database. Geoscience Australia, Australian Government. Retrieved 9 May 2008.
  2. Collins, Lindsay B.; Zhu, Zhong Rong; Wyrwoll, Karl-Heinz (1998). "Late Tertiary-Quaternary Geological Evolution of the Houtman Abrolhos Carbonate Platforms, Northern Perth Basin". In Purcell, R.; Purcell, P. (eds.). The sedimentary basins of Western Australia. Vol. 2. Perth, Western Australia: Petroleum Exploration Society of Australia. pp. 647–663. Retrieved 2 May 2008.
  3. Collins, Lindsay B.; Zhu, Zhong Rong; Wyrwoll, Karl-Heinz (2004). "Geology of the Houtman Abrolhos Islands". In Vacher, Leonard; Quinn, Terrence (eds.). Geology and hydrogeology of carbonate islands (Developments in Sedimentology 54) . Elsevier Science. pp.  811–834.

See also