干旱区生态环境知识资源中心

In this paper, the "Aqaba Formation" formed at the margins of the Aqaba Gulf, during the Quaternary, is sedimentologically studied. This formation consists mainly of clayey beds intercalated with friable silty, medium to coarse-grained sandstones, commonly with planar cross bedding, bioturbated by vertical burrows, and poorly cemented polymict conglomerate. It is also comprised of beds of clay-supported conglomerates occasionally displaying intertonguing relationships. The age of the formation is from Lower Pleistocene.

Due to the presence of greenish clay layers within the Aqaba Formation, this means that it was deposited under a stream fresh water environment. It is also noticed that the overlain Pleistocene sediments are rich in Ostracods suggesting a fresh water environment, too. Generally, wetter climatic conditions were prevailing at this period as indicated by the absence of evaporite deposits (e.g., halite and/or gypsum). The clay mineral constituents (kaolinite and illite/smectite intermixed layers) and the absence of palygorskite are supported by the wetter conditions. It is worth to mention that the essential non-clay minerals are quartz and feldspars.

This study presents the developments of the margins of the Gulf of Aqaba during Quaternary and reflects the climatic changes during this period.