We did not use the site soil as the abrader due to practical problems of drying and sieving the soil to remove material that would not pass through the saltation
Although the dunes near Parker seem to be an extension of this same sandflow path, Muhs says that saltation
couldn't carry grains of sand across the Colorado River.
Soil particles in saltation
, explains Fryrear, are too heavy to be carried by the wind.
This velocity is often called pickup velocity, or saltation
The grain texture of the wedge fillings points to transport in saltation
The positive nature of the interaction between rainfall and flow-driven erosion for the silty loam can be understood in general terms by the expectation that the loosening of soil by rainfall impact could well increase the effectiveness of the shear stresses associated with flow in removing soil into saltation
Thus, 10 inches or so marks an important boundary: the transition from saltation
to suspension (TSS).
Despite the apparent ubiquity of aeolian material in this region, radiometric information may still prove to be a powerful discriminator of landscape evolution processes here, as aeolian dust, generally composed of particles 10-100 [micro]m in diameter (Butler and Churchward 1983), may be of quite different origin to larger sand-sized particles that move by saltation
and comprise the bulk of sand dunes.
Various wind-tunnel studies and other investigations over the last few decades have shown that particles the size of typical sand grains travel in the wind principally by hopping, or saltation
While the coarse sediment should settle rapidly to the bed of the furrow, its transport along the furrow is enhanced by rolling, associated with rapid transport, whereas medium sized sediment is subject to saltation
and slower transport (Walker et al.
There have since been some minor changes, including the introduction of the soil erodibility parameter [Beta] as a surrogate variable for the original soil erodibility parameter J (Rose 1993), and incorporating the concept of saltation
stress (Bagnold 1977), which can become important when the sediment concentration is high (Fentie et al.
Five main mechanisms are identified, and defined as (1) aggregate breakdown, (2) cratering, (3) splashing, (4) splash saltation
, and (5) splash creep, several of which are illustrated with photographic and video techniques under laboratory splash tests.
It is probable that, as a result of the previous very high trampling pressures and the saltation
processes that occur during high rates of wind erosion, part of the parna material originally present as fine sand and silt-sized material (Butler 1956) is broken up into finer particles of clay and organic matter.