Application of Satellite Images to Research on Geomorphological Change of Abu Dhabi Coastline

Low-angle ramp geometry of the Abu Dhabi coastline offers an ideal setting for studying the effects of relative sea-level fluctuations on shoreline sedimentary systems and geomorphology. A late Holocene progradation rate of 0.75m/yr has been established for the Abu Dhabi sabkha system, however, a present marine transgression rate at the coastline is estimated to be 8.25m/yr based on current global sea level rise of 3.3mm/yr, it is therefore inferred that the area has entered a broadly retrogradational phase. The study utilised very high spatial resolution satellite images acquired in 2003, 2004, 2005, 2007, and 2010. They were used to trace temporal morphological changes along the coastline. Through the comparison of satellite images spits and beach ridge systems in the western part of the study area have been recognized to advance landward, over a distance of up to 207 m during a 7.5 year period. In the eastern part a landward migration of intertidal deltas has been established, and significant erosion of the upper intertidal microbial mat belt has also been proved. When combined with 7 years of fieldwork observations, these results indicate that the current sedimentary regime is broadly regressive associated with current marine transgression of the sabkha system.