Bermuda hotspot

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The Bermuda hotspot is the supposed "hotspot" (or mantle plume) proposed to explain the Bermuda Rise (a cluster of extinct volcanoes in the Atlantic Ocean, including the island of Bermuda), and also invoked by Cox and Van Arsdale to explain the origin of the Mississippi Embayment [1] [2] [3] and by Nunn to explain the Sabine Uplift (southwest of the Mississippi Embayment). [4]

A hotspot origin for the Bermuda Rise has never been strongly supported, and has been largely shut out by a detailed and tightly argued paper by Vogt and Jung. [5] (See also shorter article at MantlePlumes.org [6] )

Evidence cited against a hotspot origin include: 1) Lack of a chain of age-progressive seamounts, such as with the Hawaiian-Emperor or New England seamount chains. 2) Elongation of the Bermuda Rise at a right angle to the direction of plate motion. 3) Various problems with the ages of igneous rock attributed to the supposed hotspot and ensuing complications in the implied rate of hotspot motion.

Vogt and Jung attribute the origin of the Bermuda Rise to a reorganization of plate tectonics triggered by the closing of the Tethys Sea, but allow that until more data is obtained this is very speculative. Detailed treatment of plate-tectonic-related theory for the explanation of intraplate volcanism has recently been summarised in a book called "Plates vs Plumes: A geological controversy" by Gillian R. Foulger.[7]

See also[edit]

References[edit]

  1. ^ Cox, Randel T.; Roy B. Van Arsdale (Jan 2007). "The Mississippi's Curious Origins". Scientific American 296 (1): 76–82B. doi:10.1038/scientificamerican0107-76. 
  2. ^ Cox, Randel T.; Roy B. Van Arsdale (1997). "Hotspot origin of the Mississippi embaymenti and its possible impact on contemporary seismicity". Engineering Geology 46 (3–4): 201–216. doi:10.1016/S0013-7952(97)00003-3. 
  3. ^ Cox, Randel T.; Roy B. Van Arsdale (2002). "The Mississippi Embayment North America: A First Order Continental Structure Generated by the Cretaceaous Superplume Mantle Event". J. of Geodynamics 34 (2): 163–176. Bibcode:2002JGeo...34..163C. doi:10.1016/S0264-3707(02)00019-4. 
  4. ^ Nunn, Jeffrey A. (1990). "Relaxation of Continental Lithosphere: an Explanation for Late Cretaceous Reactivation of the Sabine Uplift of Louisiana-Texas". Tectonics 9 (2): 341–359. Bibcode:1990Tecto...9..341N. doi:10.1029/TC009i002p00341. 
  5. ^ Vogt, Peter R.; Woo-Yeol Jung (2007). "Origin of the Bermuda volcanoes and the Bermuda Rise: History, observations, models, and puzzles" (PDF). Special Paper 430: Plates, Plumes and Planetary Processes (Geological Society of America) 430: 553–591. doi:10.1130/2007.2430(27). Retrieved 2008-08-12. 
  6. ^ Vogt, Peter R.; Woo-Yeol Jung (2007-08-02). Bermuda and the Bermuda Rise – A Poor Fit to the Classical Mantle Plume Model. MantlePlumes.org. Retrieved 2008-08-12. 
  7. ^ Foulger, G.R. (2010). Plates vs. Plumes: A Geological Controversy. Wiley-Blackwell. ISBN 978-1-4051-6148-0.