The Albian to Turonian carbon isotope record from the Shilaif Basin (United Arab Emirates) and its regional and intercontinental correlation

The sedimentary record of the Arabian Shelf offers a unique opportunity to study the Cretaceous (Albian-Turonian) greenhouse climate from a palaeoequatorial perspective. In particular, hemipelagic to pelagic carbonate successions from the extensive Shilaif intra-shelf basin have the potential to produce an excellent record of carbon cycle perturbations during this interval. This study presents a 269 m thick chemostratigraphic (carbonate δ13C and δ18O) record from the Middle Albian to Early Turonian of central Abu Dhabi (United Arab Emirates), representing over 14 Myr of uninterrupted carbonate sedimentation. The Mauddud to Shilaif formations represent outer ramp to basinal intra-shelf carbonates with variations from laminated organic-rich to clean bioturbated intervals. Isotopic evidence of the latest Albian Anoxic Event (Oceanic Anoxic Event 1d), Middle Cenomanian Event I and the Cenomanian-Turonian Anoxic Event (Oceanic Anoxic Event 2) are confirmed and biostratigraphically calibrated by means of calcareous nannofossils. The carbon isotope record allows correlation with other regional records and well-calibrated records across the Tethyan Ocean and represents a significant improvement of the chronostratigraphic framework of the United Arab Emirates (Shilaif) and Oman (Natih) intra-shelf basins. The study further confirms that low carbon isotope values corresponding to the two source rock intervals in the Shilaif Formation clearly precede the isotopic expressions of Oceanic Anoxic Event 1d and Oceanic Anoxic Event 2.