Gone with the wind: dune provenance and sediment recycling in the northern Rub’ al-Khali, United Arab Emirates

Abstract

The Rub’ al-Khali dune field in southern Arabia is the largest sand sea in the world. Deciphering the palaeoenvironmental history of the Rub’ al-Khali is critical to understanding its role as a barrier to human migration, dispersal and settlement. To determine sediment provenance and transport pathways, we combined data from a geological mapping project with traditional heavy mineral optical point-counting methods, heavy mineral geochemical fingerprinting and detrital zircon U–Pb geochronology of Miocene and Quaternary sediments in the United Arab Emirates (UAE). Detrital zircon U–Pb age spectra demonstrate that most Neogene and Quaternary sediments in the UAE are ultimately sourced from the Precambrian Arabian Shield. Heavy mineral and geochemical signatures indicate that the dune sands are locally recycled from the deflation of Miocene sandstones and Quaternary siliciclastic palaeodunes exposed along the Arabian Gulf coast, whereas carbonate palaeodunes along the Gulf coast are derived from the deflation of sediments deposited by the Tigris–Euphrates River system in the Gulf during Pleistocene lowstands. In the eastern Emirates, Miocene and Quaternary alluvial fan deposits emanating from the Hajar Mountains have an ophiolitic heavy mineral signature. The data reveal new insights into the origin and development of the Rub’ al-Khali dune field. Supplementary material: A map, details of the geochronology methods and a full dataset are available at https://doi.org/10.6084/m9.figshare.c.4290350