Erosional remnants and pockets evolving from biotic-physical interactions in a Recent lower supratidal environment
Abstract: Sedimentary structures characterizing tidal depositional systems are not in all cases produced by physical dynamics alone. The activities of epibenthic cyanobacteria such as biostabilization or surface levelling may also play a significant role in structure formation. One example of bio-induced structures are 'erosional remnants and pockets', a specific surface morphology that can be observed in the lower supratidal zone of Mellum Island, southern North Sea. This surface relief rises from partwise erosion of a microbial mat-covered and biostabilized tidal surface. On the basis of detailed field measurements of the geometric dimensions of the surface relief, the tidal current system of the area and the history of formation of the morphology can be reconstructed. Erosional remnants and pockets are highly facies indicative and fossil occurrences would help in reconstruction paleo-environments.
