Eolian Systems

Modem environments in which wind is the dominant agent of deposition range from tropical to polar, the sole requirements being the availability of uncohesive sediment and an incomplete cover of vegetation. Hot, arid regions, the most favored locale for eolian accumulation, are typical of tropical to subtropical high-pressure regions, of mid-latitude rain shadows and landlocked continental interiors, and of the western margins of continents swept by cold ocean currents or subject to upwelling. Humid regions dominated by eolian deposition generally involve copious sand supply, as along beaches and broad fluvial tracts, or very cold, unstable conditions that inhibit plant growth. High-latitude deserts result from the aridity associated with divergent air flow. Pleistocene circulation of this type redistributed glacial sand into substantial dune systems in North America and northern Europe (Glennie, 1970, p. 6).