Sastrugi dunes, and the resulting drifting snow shapes are also popularly referred to as "barchans". Inuit of Canada call them "kalutoqaniq". When winds slacken, the drifted formations consolidate via sublimation and recrystallization. Subsequent winds erode kalutoqaniq into the sculptured forms of sastrugi. Inuit call large sculpturings "kaioqlaq" and small ripples "tumarinyiq". Further erosion may turn "kaioqlaq" back into drifting "kalutoqaniq". An intermediate stage of erosion is "mapsuk", an overhanging shape. On the windward side of a ridge, the base erodes faster than the top, producing a shape like an anvil tip pointing upwind. Sastrugi are more likely to form on first-year
Surface wave inversion log. The discrepancy in overall detail should have no effect in evaluating the subsurface. There are many advantages to using surface waves to image the subsurface. For one, surface wave inversion readily images low-velocity zones. Refraction methods cannot see low-velocity zones because such a zone would bend the traversing wave deeper instead of towards the surface. Surface wave inversion is also non-invasive as well as cost effective. There are a few disadvantages to this method as well. The resolution of the surface wave inversion method is not nearly as resolved as a seismic collection done in a wellbore. There is