Using Radar and Optical Satellite Images to Delineate Paleodrainages in Desert Regions: A Case Study of Saudi Arabia

Abstract

Al Saud (2023) worked on detailed cartography for all drainage systems of Saudi Arabia using SRTM DEM and topographic maps. However, a number of watercourses were noted with anomalous morphometric and sedimentological characteristics . This includes abrupt termination of stream networks, traces for dry channels and presence of linear saline soil horizons. This was attributed to the existence of paleodrainages which have been noted in several studies in the Arabian Peninsula including Saudi Arabia, and they were attributed to large global climate fluctuations that were reflected in topographic rippling and abrupt changes in terrain slopping, acting on the extinction of many watercourses and creation of others. This study characterizes paleodrainages in Saudi Arabia using remote sensing products. In this respect, SRTM DEM was used to generate detailed drainage systems; while Advanced Land Observing Satellite (ALOS) Phased Array Type L-band Synthetic Aperture Radar (PALSAR) and Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) were processed to detect paleodrainages and the relevant paleo-geomorphological features using a number of digital techniques. Seven aspects of these channels were identified and all indicating the presence of alluvial sedimentation with high porous and permeable linear features which are potential to store and transmit groundwater. They can be also routs for paleodrianagesthe intrusion of saline water on-land. The identified paleodrainages can be potential groundwater aquifers, suitable sites for groundwater artificial recharge especially where saltwater is intruded along these drainages.