Evidence of Late Holocene subsidence events in Sporades Islands: Skopelos and Alonnisos

•Along the islands coastline six to seven distinct fossil shorelines were located.•Both islands have repeatedly subsided during the last millennia, often coseismically.•Each subsidence displacement was limited to one or a few decimetres.•The displacements' recurred at intervals of some centuries.

Through this research relative sea level changes from Late Holocene until the present day were studied, in the area of Skopelos and Alonnisos Islands. The study was accomplished through methodical underwater geomorphological research in both islands and led to the location of six and seven distinct submerged fossil shorelines, in Skopelos and Alonnisos accordingly, along the islands' coastline. Both islands have been affected during the last millennia, by repeated subsidence events, often of coseimic origin. The amount of each subsidence displacement was generally limited to one or a few decimetres, with recurrence intervals of some centuries.