Niveo-aeolian deposits (from niveo: snow and aeolian:
wind) are accumulations of snow and sand that form in environments
where snow and moving sand co-exist in the winter. Snow and sand
occur in different proportions within the deposit, revealing characteristics
of the processes building the deposit.
- A layer of pure snow
indicates accumulation of snow by direct snowfall or as wind-blown
- A layer of pure sand
indicates sand movement without snow. The thickness of the layer
is an indicator of how much sand was transported.
- A layer of mixed sand
and snow indicates that sand and snow were being transported by
wind at the same time.
Pit in niveo-aeolian deposit shows layers of snow,
sand and mixed snow and sand. Major units on ruler are centimeters.
(Hoffmaster State Park in January 2005.)
Niveo-aeolian deposits occur downwind from areas of wind erosion,
at locations where sand and snow can accumulate such as the leeslopes
are products of sand transport by wind during the winter. They provide
evidence for sand movement that can be used to understand winter
processes. For example, the size, shape and thickness of sand deposited
during a sand-moving event stand out clearly on top of a fresh snow
layer. As well, the different layers visible in pits dug into niveo-aeolian
deposits can be used to interpret the recent history of aeolian
deposit is easily identified by color in this photo: sand deposited
on snow gives the area of niveo-aeolian deposition a darker (dirty)
appearance that contrasts with the white of the pure snow in the middle
left of the photo. The sand source for the deposit is a blowout on
the other side of the dune. (Hoffmaster State Park in January 2005.)