جيومورفولوجية التكوينات الرملية شرقي و جنوب شرقي الربع الخالي بالمملكة العربية السعودية

الملخص EN

about 26.1% of the Kingdom of Saudi Arabia, is considered the largest sand desert in the world.

The desert, which is 1,200 km long and 640 km wide, covers the area extending from the United Arab Emirates in the east to the foothills of the Yemen mountains in the west and from the plateau of Hadramout in the south to Gaforh sands sands Dahna desert in the north.

This study in hand aims to employ remotes sensing and GIS techniques in delineating the forms of sand in Al Rub’ al Khali desert.

Generally, different parts of Al Rub’ al Khali desert have varied forms of sand dunes.

In this respect, it was found that, While the longitudinal dunes were predominant in the western parts, the crescent-shape Barchan dunes were distributed widely in the eastern and north-eastern parts.

Meanwhile, the star-shape dunes were considerably noticed in the south-eastern parts of the study area, dome-shape sand dunes were prevalent in northern and central parts, and network-shape sand dunes concentrated in the north-eastern parts of Al Rub’ al Khali desert.

Also, the dimensions of different forms of sand dunes varied significantly, for instance, the relative height of sand dunes on average ranged from the 25, 89, 83 and 58 m in the case of dome-shape, network-shape, both of crescent-shape (Barchan) and start-shape, and longitudinal sand dunes, respectively.

Moreover, studying the distribution of sand dunes color in the study area, according Soil Atlas, revealed that the pale yellow sand was clearly associated with longitudinal form of sand dunes.

Meanwhile, red yellowish sand was associated with crescent-shape (Barchan) and star-shape sand dunes.

Additionally, brown sand was associated with crescent-shape dunes.

Also, the results of XRD analysis showed that clear dominance of metal quartz with high proportions followed by calcite.