Formation of the Wahiba Sand Sea in the Sultanate of Oman: implications of change in wind energy

The Wahiba Sand Sea is a north-south aeolian field that occupies the northeast corner of the Sultanate of Oman. Two main phases of sand dunes are conspicuous in this dune field as revealed by satellite data, namely High Sands in the north and Low Sands in the south. They are completely different in grain color and dune morphology. Granulometric and mineralogical analyses of sediments reveal more than a single source of sand supply for the two regions. Linear dune belts cover the northern dune field and complex transverse ridges predominate at the southern area. Hourly wind data from two meteorological stations at Ibra and Masirah in the north and south of the sand sea, respectively, were collected for 11 years (Jan. 2000 to Dec. 2010) in order to calculate the seasonal and annual sand drift potential along the sides of the sand sea. Results showed that wind energy is extremely high at Masirah due to the SW summer and fall monsoons, whereas at Ibra, wind energy is very low. The drop of sand drift potential (DP) from south to north is clearly observed from analyzing sand moving winds by empirical equations. The morphology of dunes and the direction of sand drift potential suggest two dune fields in the sand sea. The current pattern of wind regime in the north is presumably different from the prevailing wind during dune formation, whereas the dunes in the south were significantly formed by the recent wind regimes. This observation implies that two connected dune fields constitute the Wahiba Sand Sea.