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A summary of the oldest ages for the world's islands

Shields, O 1976 , 'A summary of the oldest ages for the world's islands' , Papers and Proceedings of the Royal Society of Tasmania, vol. 110 , pp. 35-62 , doi:

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The oldest ages of rocks on the world's islands are summarized (Oligocene or older) based on published literature. All the oceans and perhaps all the seas contain a few continental islands, indicative of debris left from continental rifting prior to ocean basin formation by seafloor spreading. The Musicians Seamounts and the Hawaiian Ridge (both Cretaceous), and the Tuamotu Islands (Eocene) are the same age as the surrounding seafloor and probably formed at the crest of the East Pacific Rise. Future drilling and dredging operations are expected to modify and add to this list, as recent volcanism may well have obscured the much older basement rocks on many islands. Thus, the faunas of the Galapagos, Mauritius, Rodriguez, and Tristan da Cunha suggest they are continental islands, while their known surface geology yields dates of only 8 m.y. or less.

Item Type: Article
Authors/Creators:Shields, O
Keywords: Royal Society of Tasmania, RST, Van Diemens Land, natural history, science, ecology, taxonomy, botany, zoology, geology, geography, papers & proceedings, Australia, UTAS Library
Journal or Publication Title: Papers and Proceedings of the Royal Society of Tasmania
ISSN: 0080-4703
DOI / ID Number:
Collections: Royal Society Collection > Papers & Proceedings of the Royal Society of Tasmania
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