Eolian Environments

Eolianites (ancient dune deposits) are generally devoid of body fossils, but trace fossils may be abundant and diverse. The Entradichnus Ichnofacies represents the recurrent assemblages of burrows, trails, and trackways produced by both invertebrates and vertebrates that characterize coastal and inland dune paleoenvironments. The gently sloping, erosional, stoss side of a dune tends to exhibit more diverse, more delicate, and less deformed repichnial, pascichnial, and domichnial traces than does the more steeply dipping, depositional, slip-face side of a dune, where most of the traces are repichnia that exhibit deformation by sediment slippage and collapse. Trace-fossil associations and ichnofabrics in eolianites lend important information to paleoecologic and paleoclimatic studies because they provide evidence of the types of organisms inhabiting the dunes and the seasonal nature of their activity in monsoonal climates.