Pole shift hypothesis

"Polar Shift" redirects here. For the Clive Cussler novel, see Polar Shift (novel). For the Antarctica benefit compilation, see Polar Shift (album).
This article is about the hypothesis of pole shift in its historical context. For a description of the modern scientific understanding, see true polar wander. For magnetic poles, see Geomagnetic reversal.

The cataclysmic pole shift hypothesis suggests that there have been geologically rapid shifts in the relative positions of the modern-day geographic locations of the poles and the axis of rotation of the Earth, creating calamities such as floods and tectonic events.[1]

There is evidence of precession and changes in axial tilt, but this change is on much longer time-scales and does not involve relative motion of the spin axis with respect to the planet. However, in what is known as true polar wander, the solid Earth can rotate with respect to a fixed spin axis. Research shows that during the last 200 million years a total true polar wander of some 30° has occurred, but that no super-rapid shifts in the Earth's pole were found during this period.[2] A characteristic rate of true polar wander is 1° or less per million years.[3] Between approximately 790 and 810 million years ago, when the supercontinent Rodinia existed, two geologically rapid phases of true polar wander may have occurred. In each of these, the magnetic poles of the Earth shifted by ~55°.[4]

Definition and clarification

The geographic poles are defined by the points on the surface of the Earth that are intersected by the axis of rotation. The pole shift hypothesis describes a change in location of these poles with respect to the underlying surface – a phenomenon distinct from the changes in axial orientation with respect to the plane of the ecliptic that are caused by precession and nutation, and is an amplified event of a true polar wander.

Pole shift hypotheses are not connected with plate tectonics, the well-accepted geological theory that the Earth's surface consists of solid plates which shift over a viscous, or semifluid asthenosphere; nor with continental drift, the corollary to plate tectonics which maintains that locations of the continents have moved slowly over the face of the Earth,[5] resulting in the gradual emerging and breakup of continents and oceans over hundreds of millions of years.[6]

Pole shift hypotheses are not the same as geomagnetic reversal, the periodic reversal of the Earth's magnetic field (effectively switching the north and south magnetic poles).

Speculative history

In popular literature, many conjectures have been suggested involving very rapid polar shift. A slow shift in the poles would display the most minor alterations and no destruction. A more dramatic view assumes more rapid changes, with dramatic alterations of geography and localized areas of destruction due to earthquakes and tsunamis.

Early proponents

An early mention of a shifting of the Earth's axis can be found in an 1872 article entitled "Chronologie historique des Mexicains"[7] by Charles Étienne Brasseur de Bourbourg, a specialist in Mesoamerican codices who interpreted ancient Mexican myths as evidence for four periods of global cataclysms that had begun around 10,500 BCE. In 1948, Hugh Auchincloss Brown, an electrical engineer, advanced a hypothesis of catastrophic pole shift. Brown also argued that accumulation of ice at the poles caused recurring tipping of the axis, identifying cycles of approximately seven millennia.[8][9]

In his controversial 1950 work Worlds in Collision, Immanuel Velikovsky postulated that the planet Venus emerged from Jupiter as a comet. During two proposed near approaches in about 1,450 BCE, he suggested that the direction of the Earth's rotation was changed radically, then reverted to its original direction on the next pass. This disruption supposedly caused earthquakes, tsunamis, and the parting of the Red Sea. Further, he said near misses by Mars between 776 and 687 BCE also caused the Earth's axis to change back and forth by ten degrees. Velikovsky cited historical records in support of his work, although his studies were generally ridiculed by the scientific community.[10]

Charles Hapgood is now perhaps the best remembered early proponent. In his books The Earth's Shifting Crust (1958) (which includes a foreword by Albert Einstein)[11][12] and Path of the Pole (1970), Hapgood, building on Adhemar's much earlier model, speculated that the ice mass at one or both poles over-accumulates and destabilizes the Earth's rotational balance, causing slippage of all or much of Earth's outer crust around the Earth's core, which retains its axial orientation. Based on his own research, Hapgood argued that each shift took approximately 5,000 years, followed by 20,000- to 30,000-year periods with no polar movements. Also, in his calculations, the area of movement never covered more than 40 degrees. Hapgood's examples of recent locations for the North Pole include Hudson Bay (60˚N, 73˚W), the Atlantic Ocean between Iceland and Norway (72˚N, 10˚E) and Yukon (63˚N, 135˚W). However, in his subsequent work The Path of the Pole, Hapgood conceded Einstein's point that the weight of the polar ice would be insufficient to bring about a polar shift. Instead, Hapgood argued that the forces that caused the shifts in the crust must be located below the surface.[13] Hapgood wrote to a Canadian librarian, Rand Flem-Ath, encouraging him in his pursuit of scientific evidence to back Hapgood's claims and in his expansion of the hypothesis. Flem-Ath published the results of this work in 1995 in When the Sky Fell co-written with his wife.[14]

In 1974 Flavio Barbiero, an engineer and explorer, theorized that shifting of the Earth's axis took place 11,000 years ago and caused what was subsequently recorded in myth as the destruction of Atlantis and Mu. He suggested that shifting was probably caused by the impact of a comet on the Earth's surface and that the current position of Atlantis has to be sought under the Antarctic ice sheet.[15]

Recent conjectures

The field has attracted a number of authors offering a variety of evidence.

In the 1970s and 1980s a series of books not intended as fiction by former Washington newspaper reporter Ruth Shick Montgomery elaborates on Edgar Cayce readings.[16]

In 1997 Richard W. Noone published 5/5/2000, ICE: The Ultimate Disaster. This book argued that a cataclysmic shift of the Earth's ice cap covering Antarctica caused by a planetary alignment and solar storms, would lead to crustal displacement on May 5, 2000.[17]

In 1998 retired civil engineer James G. Bowles proposed in Atlantis Rising magazine a mechanism by which a polar shift could occur. He named this Rotational-Bending, or the RB-effect. He hypothesized that combined gravitational effects of the Sun and the Moon pulled at the Earth's crust at an oblique angle. This force steadily wore away at the underpinnings that linked the crust to the inner mantle. This generates a plastic zone that allows the crust to rotate with respect to the lower layers. Centrifugal forces would act on the mass of ice at the poles, causing them to move to the equator.[18]

Books on this subject have been published by William Hutton, including the 1996 book Coming Earth Changes: Causes and Consequences of the Approaching Pole Shift (ISBN 0876043619), which compared geologic records with the psychic readings of Edgar Cayce and predicted catastrophic climate changes before the end of 2001. In 2004 Hutton and co-author Jonathan Eagle published Earth's Catastrophic Past and Future: A Scientific Analysis of Information Channeled by Edgar Cayce (ISBN 1-58112-517-8), which summarizes possible mechanisms and the timing of a future pole shift.

Scientific research

Main article: True polar wander

While there are reputable studies showing that true polar wander has occurred at various times in the past, the rates are much smaller (1° per million years or slower) than predicted by the pole shift hypothesis (up to 1° per thousand years).[2][3][19] Analysis of the evidence does not lend credence to Hapgood's hypothesized rapid displacement of layers of the Earth.[20] Data indicate that the geographical poles have not deviated by more than about 5° over the last 130 million years, contradicting the hypothesis of a cataclysmic polar wander event.[21] More rapid past possible occurrences of true polar wander have been measured: from 790 to 810 million years ago, true polar wander of approximately 55° may have occurred twice.[4] There is no known physical evidence of more rapid shifts occurring at any point during Earth's history.

See also

Notes

  1. ↑ Kiger, Patrick J. Ends of the Earth: Shifting of the Poles. National Geographic. Retrieved 2009-11-22.
  2. 1 2 Besse, Jean; Courtillot, Vincent (November 2002). "Apparent and true polar wander and the geometry of the geomagnetic field over the last 200 Myr". Journal of Geophysical Research: Solid Earth. 107 (B11): EPM 6–1. Bibcode:2002JGRB..107.2300B. doi:10.1029/2000JB000050.
  3. 1 2 Andrews, J. A. (August 10, 1985). "True polar wander - An analysis of cenozoic and mesozoic paleomagnetic poles". Journal of Geophysical Research. 90 (B9): 7737–7750. Bibcode:1985JGR....90.7737A. doi:10.1029/JB090iB09p07737.
  4. 1 2 Maloof, Adam C.; et al. (2006). "Combined paleomagnetic, isotopic, and stratigraphic evidence for true polar wander from the Neoproterozoic Akademikerbreen Group, Svalbard, Norway". Geological Society of America Bulletin. 118 (9): 1099–1124. Bibcode:2006GSAB..118.1099M. doi:10.1130/B25892.1.
  5. ↑ Scotese, C. R. "The PaleoMap Project". Retrieved 2010-05-04.
  6. ↑ Cottrell, R. D.; Tarduno, J. A. (June 30, 2000). "Late Cretaceous True Polar Wander: Not So Fast". Science. 288 (5475): 2283. doi:10.1126/science.288.5475.2283a. Retrieved 2010-05-04.
  7. ↑ "Chronologie historique des Mexicains", L'ethnographie (in French), Paris, France: Société d'Ethnographie, 7: 77–85, 1871, retrieved 2009-11-08
  8. ↑ Brown, Hugh Auchincloss (1967). Cataclysms of the Earth. Twayne Publishers.
  9. ↑ "Science: Can the Earth Capsize?". Time. September 13, 1948. Retrieved 2009-11-08.
  10. ↑ Alexander, Robert E. (2005). Robert F. Morgan, ed. The Velikovsky Affair: Case History of Iatrogenic Behavior in Physical Science. Morgan Foundation Publishers. pp. 21–24. ISBN 1-885679-11-4.
  11. ↑ Charles H. Hapgood (1958). Earth's Shifting Crust: A Key to Some Basic Problems of Earth Science, introduction by Einstein. Pantheon Books. OCLC 150491536. Archived from the original on 2013.
  12. ↑ Martinez-Frias, Jesus; Hochberg, David; Rull, Fernando (December 13, 2005). "Contributions of Albert Einstein to Earth Sciences: A review in Commemoration of the World Year of Physics". Naturwissenschaften. 93 (2): 66–71. arXiv:physics/0512114Freely accessible. Bibcode:2006NW.....93...66M. doi:10.1007/s00114-005-0076-8. PMID 16453104.
  13. ↑ Palmer, Trevor (2003). Perilous planet earth: catastrophes and catastrophism through the ages. Cambridge University Press. pp. 113–114. ISBN 0-521-81928-8.
  14. ↑ Flem-Ath, Rand, Flem-Ath, Rose. When The Sky Fell: In Search of Atlantis (introduction by Colin Wilson, London: Weidenfeld & Nicolson, 1995). ISBN 0-297-81628-4
  15. ↑ Barbiero, Flavio. Una Civiltà Sotto Ghiaccio. Casa Editrice Nord, Realtà scientifiche. ISBN 88-429-1168-2.
  16. ↑ Threshold to Tomorrow, (1984) ISBN 978-0-449-20182-4 ISBN 0449201821; Strangers Among Us, (1979); Aliens Among Us, (1985) and The World to Come: The Guides' Long-Awaited Predictions for the Dawning Age, (1999).
  17. ↑ Noone, Richard W. (May 20, 1997). 5/5/2000, ICE: The Ultimate Disaster. New York City: Three Rivers Press. ISBN 0-609-80067-1. Preface, Table of Contents, Appendices.
  18. ↑ Bowles, James (1999). "Hapgood Revisited". Atlantis Rising (18). Retrieved 2009-11-09.
  19. ↑ Hoffman, P. (1999). "The break-up of Rodinia, birth of Gondwana, true polar wander and the snowball Earth". Journal of African Earth Sciences. 28 (1): 17–33. Bibcode:1999JAfES..28...17H. doi:10.1016/S0899-5362(99)00018-4.
  20. ↑ Brass, Michael (July–August 2002). "Tracing Graham Hancock's Shifting Cataclysm". Skeptical Inquirer. 26.4. Retrieved 2010-04-19.
  21. ↑ Tarduno, John A.; Smirnova, Alexei V. (January 15, 2001). "Stability of the Earth with respect to the spin axis for the last 130 million years". Earth and Planetary Science Letters. 184 (2): 549–553. Bibcode:2001E&PSL.184..549T. doi:10.1016/S0012-821X(00)00348-4.

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