The most diagnostic features of the eolian cross-bedding of Mustang Island are: 1) the large percentage (27%) of cross-beds that have dip angles greater than 30 degrees and the high mean inclination (24 degrees ); and 2) the bimodality of dip directions with modes to the N. and WSW. The bimodality is attributed to the migration of asymmetrical pyramidal dunes, a dune form that develops as an intermediate step in the transformation of barchan to longitudinal dunes as sand migrates inland. The mean standard deviation of dip azimuths of Mustang Island cross-beds (75 degrees ) is intermediate between most fluvial and marine cross-beds; it is based, however, on a bimodal distribution. The Mustang Island dunes indicate that eolian cross-bedding need not be either highly unidirectional or highly dispersed, and need not be characterized by sets of great thickness.

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