The Ghalilah Formation, UAE provides a complete and continuous equatorial shallow-water carbonate sequence through the Upper Triassic to Lower Jurassic interval. In higher latitudes, this interval is frequently associated with widespread ocean acidification evidenced by a lack of carbonates or a hiatus in deposition. The data presented here in contrast show evidence for aragonite supersaturation at the Triassic–Jurassic boundary in the equatorial Tethys. δ13Ccarb shows a characteristic negative excursion with values as low as −2.8‰ just below the boundary. Deposition of fossiliferous limestones in this location persisted into the latest Rhaetian through the initial negative carbon isotope excursion.
Supplementary material: δ13Ccarb data from bulk rock and a detailed stratigraphic log with sample locations are available at https://doi.org/10.6084/m9.figshare.c.3277283.