Using Landsat-TM Images in Mapping ? Al-Majnonah ?Sabkha Distribution Along the Red Sea Coast, Southeaof Al-Lith, Kingdom of Saudi Arabia

Abstract

Red Sea coast is well known for sabkha occurrences. An area was selected to the southeast of Al-Lith City in the southern half of the Red Sea. Part of the area was previously studied and found that the sabkha deposit is mainly sedimentologically arenaceous, composed of sand with clay lenses. This previously studied sabkha was examined by digital image processing of Landsat Thematic Mapper (TM) digital data and new maps were produced. Images used in this study followed two image enhancement techniques, namely, false colour composite (FCC) and principal components analysis (PCA). The PCA enables data compression and guides delineation certain terrain features of interest that are otherwise indiscernible. The FCC image could delineate the contact between the sabkha and non-sabkha areas, while the PCA imagery is useful in distinguishing the four main types of sabkhas in the area. The newly created maps exhibiting sabkha distribution in the area showed that the Landsat TM digital data plays an important role in sabkha studies along the Red Sea coast and any similar areas.