Encyclopedia of Planetary Landforms

2015 Edition
| Editors: Henrik Hargitai, Ákos Kereszturi

Ridge in Current Shadow

  • Henrik Hargitai
  • Nicholas Lancaster
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-3134-3_531


Elevated sediment structure on the downflow side of small topographic obstacles.


A type of  drift deposit, a type of  obstacle dune, inner part of a  current crescent.


Less Frequently used Synonyms

 Comet mark (defined as “obstacle marks with an erosional tail of considerable length relative to their width”) (Werner and Newton 1975);  Current shadow (Bishop 2011; Allen 1982);  Rat tail (cm-scale forms in subglacial meltwater scoured bedrock; Prest 1983);  Remnant rock ridge (Sharpe and Shaw 1989); (Bagnold 1954, p. 159);  Scour remnant ridge (e.g., in snow; Allen 1965);  Shadow ridge (Hesp 1981).


Elongated triangular-shaped aeolian deposit in the lee side of topographic obstacles, in which the apex is oriented downwind (Greeley et al. 2006; Blake et al. 2013), produced by accumulated material that may form elevated structure, or a plain that differs only in albedo from its surroundings.


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.NASA Ames Research Center/NPPMoffett FieldUSA
  2. 2.Division of Earth and Ecosystem SciencesDesert Research InstituteRenoUSA