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| url = https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2011GL049843
| url = https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2011GL049843
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. In addition, it permits dating of changes in ice flow and the establishment of changes in ice thickness.<ref name="ConwayHall99">{{cite journal|last=Conway |first=H. |author2=B. Hall |author3=G. Denton |author4=A. Gades |author5=E.D. Waddington |title=Past and future grounding-line retreat of the West Antarctic Ice |journal=[[Science_(journal)|Science]] |year=1999 |volume=286 |issue=5438 |pages=280–283 |doi=10.1126/science.286.5438.280|pmid=10514369|url=https://science.sciencemag.org/content/286/5438/280.abstract}}</ref> The effect was first predicted by Charles F. Raymond.<ref name=steig2009>{{cite journal |author=Raymond C.R.|title=Deformation in the vicinity of ice divides |journal=[[Journal of Glaciology (journal)|Journal of Glaciology]] |volume=29 |pages=357–373 |year=1983 |issue= 103|doi=10.1017/S0022143000030288 |doi-access=free }}</ref> Raymond Arches and the Raymond Effect have been observed at numerous other ice divides e.g. [[Siple Dome]];
. In addition, it permits dating of changes in ice flow and the establishment of changes in ice thickness.<ref name="ConwayHall99">{{cite journal|last=Conway |first=H. |author2=B. Hall |author3=G. Denton |author4=A. Gades |author5=E.D. Waddington |title=Past and future grounding-line retreat of the West Antarctic Ice |journal=[[Science_(journal)|Science]] |year=1999 |volume=286 |issue=5438 |pages=280–283 |doi=10.1126/science.286.5438.280|pmid=10514369|url=https://science.sciencemag.org/content/286/5438/280.abstract}}</ref> The effect was first predicted by Charles F. Raymond.<ref name=steig2009>{{cite journal |author=Raymond C.F.|title=Deformation in the vicinity of ice divides |journal=[[Journal of Glaciology (journal)|Journal of Glaciology]] |volume=29 |pages=357–373 |year=1983 |issue= 103|doi=10.1017/S0022143000030288 |doi-access=free }}</ref> Raymond Arches and the Raymond Effect have been observed at numerous other ice divides e.g. [[Siple Dome]];
<ref name="Siple2000">{{cite journal|last1=Nereson|first1=N.A.|last2=Raymond|first2=C.F.|last3=Jacobel|first3=R.W.|last4=Waddington|first4=E.D.
<ref name="Siple2000">{{cite journal|last1=Nereson|first1=N.A.|last2=Raymond|first2=C.F.|last3=Jacobel|first3=R.W.|last4=Waddington|first4=E.D.
|display-authors=2|title=The accumulation pattern across Siple Dome, West Antarctica, inferred from radar-detected internal layers |journal=[[Journal of Glaciology (journal)|Journal of Glaciology]]
|display-authors=2|title=The accumulation pattern across Siple Dome, West Antarctica, inferred from radar-detected internal layers |journal=[[Journal of Glaciology (journal)|Journal of Glaciology]]

Revision as of 23:39, 14 December 2020

Raymond Effect is a flow effect in ice sheets, occurring at flow divides, which gives rise to disturbances in the stratigraphy, showing unusual arches or anticlines called Raymond Arches.[1] The stratigraphy is detected by radio-echo sounding. The Raymond effect arises from the unusual flow properties of ice. It is of importance because it provides field evidence for the flow properties of ice [2] . In addition, it permits dating of changes in ice flow and the establishment of changes in ice thickness.[3] The effect was first predicted by Charles F. Raymond.[4] Raymond Arches and the Raymond Effect have been observed at numerous other ice divides e.g. Siple Dome; [5] Fletcher Ice Rise, Berkner Island[6] [7]; Roosevelt Island [3][7]; Korff Ice Rise. [8]


Ice viscosity is stress-dependent, and in zones where the (deviatoric) stresses are low, the viscosity becomes very high. Near the base of ice-sheets, stress is proportional to the surface slope, at least when averaged over a suitable horizontal distance. At the flow divide, the surface slope is zero, and calculations show that the viscosity increases[4]. This diverts ice flow laterally, and is the cause of the characteristic anticlines, which are in effect draped over the high viscosity area.

References

  1. ^ Vaughan, David G.; Hugh F. J. Corr; Christopher S. M. Doake; Ed. D. Waddington (25 March 1999). "Distortion of isochronous layers in ice revealed by ground-penetrating radar". Nature. 398 (6725): 323–326. doi:10.1038/18653.
  2. ^ Gillet-Chaulet, F.; et al. (2011). "In-situ quantification of ice rheology and direct measurement of the Raymond Effect at Summit, Greenland using a phase-sensitive radar". Geophysical Research Letters. 38. doi:10.1029/2011GL049843.
  3. ^ a b Conway, H.; B. Hall; G. Denton; A. Gades; E.D. Waddington (1999). "Past and future grounding-line retreat of the West Antarctic Ice". Science. 286 (5438): 280–283. doi:10.1126/science.286.5438.280. PMID 10514369.
  4. ^ a b Raymond C.F. (1983). "Deformation in the vicinity of ice divides". Journal of Glaciology. 29 (103): 357–373. doi:10.1017/S0022143000030288.
  5. ^ Nereson, N.A.; Raymond, C.F.; et al. (2000). "The accumulation pattern across Siple Dome, West Antarctica, inferred from radar-detected internal layers". Journal of Glaciology. 46 (152): 75–87. doi:10.3189/172756500781833449.
  6. ^ Hindmarsh, R.C.A.; King, E.C.; Mulvaney, R.; et al. (2011). "Flow at ice-divide triple junctions: 2. Three-dimensional views of isochrone architecture from ice-penetrating radar surveys". Journal of Geophysical Research. 116 (F02024). doi:10.1029/2010JF001785. Retrieved 19 August 2020.
  7. ^ a b Kingslake, J.; Hindmarsh, R.C.A; Aðalgeirsdóttir, G.; et al. (2014). "Full-depth englacial vertical ice-sheet velocities measured using phase-sensitive radar". Journal of Geophysical Research. 119. doi:10.1029/2014JF003275.
  8. ^ Kingslake, J.; Martín, C.; et al. (2016). "Ice‐flow reorganization in West Antarctica 2.5 kyr ago dated using radar‐derived englacial flow velocities". Geophysical Research Letters. 43 (17): 9103–9112. doi:10.1002/2016GL070278.