Sastrugi Sastrugi Sastrugi, or zastrugi, are sharp irregular grooves or ridges formed on a snow surface by wind erosion, saltation of snow particles, and deposition, and found in polar and open sites such as frozen lakes in cold temperate regions. The ridges are usually perpendicular to the prevailing winds; they are steep on the windward side and sloping to the leeward side. Smaller irregularities of this type are known as ripples (small, ~10 mm high) or wind ridges. Larger features are especially troublesome to skiers and snowboarders. Traveling on the irregular surface of sastrugi can be very tiring, and can risk
Surface wave inversion also the possibility for non-unique solutions to dispersion curves (several sets of parameters can yield the same dispersion curve). Surface wave inversion is becoming a valuable tool in evaluating the near subsurface. Surface waves found on seismograms can now be a useful by product of seismic exploration surveys instead of a waste product. Furthermore, it is more budget friendly because the use of an active energy source is not needed. Also, it is useful in detecting low velocity zones in the subsurface that are undetectable by refraction methods. It is most effective in estimating shear velocity, density, and thickness of