Large-Scale Bedforms on Volcaniclastic Aprons Around the Aeolian Islands (Italy)

Large-scale bedforms, with wavelengths ranging from several tens of metres to over 1 km and wave heights ranging from a few metres to tens/hundreds of metres were observed on multibeam bathymetry in the median and lower part of submarine volcaniclastic aprons surrounding the Aeolian Islands, where a marked decrease in slope gradients below 4°-8° is present. The bedforms are characterized by crest-lines with an arcuate or sinuous shape, trending roughly perpendicular to the maximum slope direction. Based on their size, geometry and texture, they can be interpreted as coarse-grained sediment waves, which are also found in the proximal part of other modern and ancient turbidite systems. In the study areas, they are found within channelized features or on fan-shaped features lying at or close to major sedimentary sources, such as subaerial/submarine depressions left by sector collapses.