Continental fragment

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Continental crustal fragments or microcontinents are fragments of continents thought to have been broken off from the main continental mass forming distinct islands, possibly several hundred kilometers from their place of origin.[1] They therefore are not considered to contain a craton.

Some are fragments of Gondwanaland or other ancient cratonic continents: Zealandia, which includes New Zealand and New Caledonia; Madagascar; the northern Mascarene Plateau, which includes the Seychelles; the island of Timor,[2]etc. Other islands, such as several in the Caribbean Sea, are composed largely of granitic rock as well, but all continents contain both granitic and basaltic crust, and there is no clear boundary as to which islands would be considered microcontinents under such a definition. The Kerguelen Plateau, for example, is largely volcanic, but is associated with the breakup of Gondwanaland and is considered to be a microcontinent,[3][4][5] whereas volcanic Iceland and Hawaii are not. The British Isles, Sri Lanka, Borneo, and Newfoundland are margins of the Laurasian continent which are only separated by inland seas flooding its margins.

Several islands in the eastern Indonesian archipelago are considered continental fragments, although this is still a controversial theory. These include Sumba, Timor (Nusa Tenggara), Banggai-Sulu Islands (Sulawesi), Obi, southern Bacan, and the Buru-Seram-Ambon complex (Maluku) are all thought to be continental crustal fragments.[6]

[edit] References

  1. ^ Monk,, K.A.; Fretes, Y., Reksodiharjo-Lilley, G. (1996). The Ecology of Nusa Tenggara and Maluku. Hong Kong: Periplus Editions Ltd., pages 41-43. ISBN 962-593-076-0. 
  2. ^ Monk,, K.A.; Fretes, Y., Reksodiharjo-Lilley, G. (1996). The Ecology of Nusa Tenggara and Maluku. Hong Kong: Periplus Editions Ltd., pages 27-29. ISBN 962-593-076-0. 
  3. ^ UT Austin scientist plays major rule in study of underwater "micro-continent". Retrieved on 2007-07-03
  4. ^ REFERENCE Could we eventually uncover a lost civilization on the sunken Kerguelen continent? Retrieved on 2007-07-03
  5. ^ http://news.bbc.co.uk/1/hi/sci/tech/353277.stm Retrieved on 2007-07-03
  6. ^ Monk,, K.A.; Fretes, Y., Reksodiharjo-Lilley, G. (1996). The Ecology of Nusa Tenggara and Maluku. Hong Kong: Periplus Editions Ltd., page 41. ISBN 962-593-076-0. 
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