Interplay between sea level rise and tectonics in the Holocene evolution of the Sant’Eufemia Plain (Calabria)

The western Calabria region is characterized by high relief rocky coasts alternating with large plains, such as the St Eufemia plain. The Holocene history of this plain has been reconstructed by integrating morphostratigraphic, chronostratigraphic and palaeoenvironmental analyses. A new core, 20-m long, drilled in the modern plain and chronologically constrained through ten 14 C datings, proved to cover the last 9500 years. Micropaleontological and sedimentological analyses, coupled with palynological investigation, allowed the evolution of the environments to be reconstructed in detail. During the early Holocene, an open lagoon established along the coast over the alluvial environment left by the late Pleistocene sea level low stand. At ca. 8600 yr BP the growth of barrier ridges drove the development of marshy areas, bounded at their back by a Pleistocene marine terrace +30/40 m high. Humid conditions, with small lakes and wetlands, persisted in the narrow coastal plain along the middle-late Holocene. Between 2500 and 1500 yr BP, the increase in the alluvial and littoral sedimentation triggered the final phase of coastline progradation. Comparison between the sedimentary evolution of the St Eufemia plain and the Holocene sea-level rise history sheds lights on the tectonic behavior of this coastal sector which seems to have experienced a more intense uplift in the early Holocene and a tendency to stability in the middle-late Holocene.