Latest Pleistocene and Holocene dune construction at the north-eastern edge of the Rub Al Khali, United Arab Emirates

Optical dating of two dune profiles developed in linear dunes in Ras Al Kha imah, United Arab Emirates, has been used to establish the timing and rate of dune accretion. One section at Awafi was over 17 m high, while that at I dhn was over 40 m high. The Awafi dune appears to have accumulated very rap idly approximate to 10000 years ago, with a vertical accumulation rate of a bout 3.3 m ka(-1). The Idhn dune appears to have accumulated over the past 1000 years, with 20 m of sediment accumulating in a time period of about 27 0 years. The Awafi dune may have accumulated in response to the transgressi on of the Persian Gulf by rising sea levels in late Pleistocene and Holocen e times. The Idhn dune may have accumulated rapidly because of intensified human activity, a short-lived climatic event, or because it may periodicall y be reactivated after erosion by fluvial action at its base.