Early Jurassic eolian dune field, Pomperaug basin, Connecticut and related synrift deposits: Stratigraphic framework and paleoclimatic context

The discovery of an extensive eolian sandstone in the Pomperaug basin, Connecticut is noteworthy because it is the most significant occurrence of eolian rocks in the continental rifts of the Newark Supergroup south of the Fundy basin, Canada. Climate-sensitive rocks provide important constraints for the influence of supercontinent landmass configurations on models of early Mesozoic Pangaean climate. The sedimentary structures and textures in the Pomperaug basin sandstone compare favorably with modern and ancient eolian sands. The eolian sandstone is traceable for at least 5 km and occupies a stratigraphic interval that is dominated by arid facies in the Pomperaug and Hartford basins, indicating that the eolian deposit is indicative of regional climate. The eolian sands were stabilized by a return to more humid conditions and subsequently buried beneath a thick, basin-wide basalt flow, preserving the dune field. Also described are related synrift eolian sandstones from the Hartford (Connecticut, USA), Fundy (Nova Scotia, Canada), and Argana (Morocco) basins. Using revised paleolatitude models for the Pangaean rifts, the distribution of eolian sandstones suggests that the Norian–Hettangian world had zonal climate belts with modified latitudinal gradients.