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317; Lecture 20
| Term | Definition |
|---|---|
| Lag deposits | a residual accumulation of coarse rock fragments on a surface after the finer material has been blown away by the wind |
| Desert pavement | forms in desert environments |
| Stone pavement | forms in alpine and periglacial environments with sparse vegetation |
| Deflation hollows | depressions that form unconsolidated material as fine grained sediment is carried away by deflation |
| Yardangs | streamlined, sharp, and sinuous ridges that extend parallel to the wind and are separated by parallel depressions |
| Ventifacts | stones shaped by the erosive action of windblown sand |
| Dunes | collections of loose sand deposited by the wind |
| Stoss | upwind side of dune, gentle slope |
| Lee | downwind side of dune, steep slope |
| Free dunes | deposited in flat, expansive areas with little obstructions Deposited by sedimentation and accretion |
| Anchored dunes | deposition controlled by vegetation and topography |
| Dunefields | sand covers area <30,000 kilometers squared |
| Sand sea | sand covers area >30,000 kilometers squared |
| Crescentic/Barchan dunes | crescent-shaped mounds that bend away from wind direction, unidirectional wind |
| Linear/Transverse dunes | straight or slightly sinuous ridges longer than they are wide, bidirectional wind but one direction is dominant over the other |
| Star dunes | radially symmetrical, arms radiate from a central mound, multidirectional wind |
| Dome dunes | oval, circular mounds lacking a slipface, rare and not well understood |
| Parabolic dunes | u-shaped, similar form to crescentic, but the dune bends upwind instead of downwind |
| Loess | a loosely compacted yellowish-brown deposits of windblown silt particles |