High‐resolution facies analysis of a coastal sabkha in the eastern Gulf of Salwa (Qatar): A spatio‐temporal reconstruction

Sabkhas are key landforms along the southern coast of Arabian Gulf and represent modern analogues for depositional diagenetic processes controlling properties quality ancient hydrocarbon-bearing carbonates. While previous investigations coastal sabkhas in Qatar have mainly focused on dolomitization processes, presented here is one first studies reconstructing facies changes formation great detail. In sabkha Al-Kharayej (Gulf Salwa), fifteen different types were distinguished based twelve sediment cores, two trenches, as well grain-size distribution, X-ray powder diffraction, thin section microfossil analyses. Age estimates seventy-eight 14C-AMS optically stimulated luminescence data. The parasequence comprises pre-transgressive dune sands, a thin, transgressive layer reworked material, mid-energy open-coast to open-lagoon facies, low-energy lagoon saline lake (salina: swallow-tail gypsum mush) supratidal characterized by overprinting (buckled crusts halite crust). Transgressive marine flooding created sedimentation after ca 7000 cal yr bp, followed initial spit at northern end beginning relative sea-level highstand (6000 bp). This main outer prograded southward more narrow, spit, diverted landward, closing small 4500 4000 bp. falling longshore drift intensified extension widening became shallow. At 2000 1500 had almost closed lagoon, leading salina and, finally, conditions. It shown how specific local conditions (coastline orientation; wind, wave, tidal energy, drift; relief; sources) spit-controlled that genetically distinct from classical model shore-perpendicular accumulation coarser during high tides or storms.