Unlike modern macropodids, which hop ( either bipedally or quadrupedally ), sthenurines seem to have abandoned saltation as a means of locomotion.
32.
Particles move by rolling, sliding, or saltation ( bouncing or jumping of grains ) at velocities less than that of the surrounding flow.
33.
:: * " Saltation " is a method of sediment transport that briefly suspends particles and then drops them creating a forward bouncing pattern.
34.
Saltation normally lifts sand-size particles no more than one centimeter above the ground and proceeds at one-half to one-third the speed of the wind.
35.
Among the mammals saltation is commonly used among macropods ( kangaroos and their relatives ), jerboas, springhares, kangaroo rats, hopping mice, gerbils, and sportive lemurs.
36.
:* A " skip mark " is part of a series of linear tool marks left by an object that skipped along the bottom of a stream by saltation.
37.
Saltation is responsible for the majority ( 50 70 % ) of wind erosion, followed by suspension ( 30 40 % ), and then surface creep ( 5 25 % ).
38.
If a particle has obtained sufficient speed from the acceleration by the fluid, it can eject, or " splash ", other particles in saltation, which propagates the process.
39.
Rolling is the primary mode of transport in gravel-bed streams, while saltation in which grains hop over the bed in a series of low trajectories is largely restricted to sands and small gravels.
40.
:Our article, Saltation ( geology ), is not very detailed or numerical; but I found this textbook : " Pneumatic conveying of solids : a theoretical and practical approach ".
