Three-dimensional properties of laboratory sand waves obtained from two-dimensional autocorrelation analysis.

A comprehensive data set of 3-D sand waves developing from a flat bed to equilibrium stage (known as the research program SWAT.nz - Sand Waves and Turbulence New Zealand) was obtained during investigations in a 5-ft-wide flume at The University of Auckland. The recorded sand bed is treated as a continuous field of sand-bed elevations, rather than subdivided into discrete sand waves. Aiming at 3-D interpretation of the random field of sand-bed elevations, 2-D autocorrelation analyses are introduced. It is shown that the 2-D autocorrelation function approach is a useful tool to depict 3-D characteristics of sand waves and their further potential is outlined.