INFRARED STIMULATED LUMINESCENCE DATING OF SANDS FROM THE CRONESE BASINS, MOJAVE DESERT

Potassium-rich feldspars separated from aeolian sands from the East an d West Cronese Basin have been dated by infra-red stimulated luminesce nce. Sands from shoreline-reworked aeolian dune ridges in the West Cro nese Basin suggest that Late Holocene playa lakes have existed in the basin within the last 2000 years. Four dates from these ridges suggest that a phase of aeolian deposition and stabilisation occurred 150-250 years ago. A date of 250 +/- 75 years on a yardang formed from horizo ntally bedded sand, however, implies that at least a metre of erosion in the West Cronese Basin has occurred since that time, in response to a dominant southwesterly wind. Late Pleistocene dates ranging from 18 ,850 to 23,350 years were obtained from an aeolian unit in the East Cr onese Basin giving limiting ages on wavecut shorelines formed in the d eposit. This aeolian sand appears to have been deposited and stabilise d at a similar time to part of the nearby Cat Dune sand ramp.