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Interplay between sea level rise and tectonics in the Holocene evolution of theSt. Eufemia Plain (Calabria, Italy)

Maria Rosaria Ruello1, Aldo Cinque1, Valentino Di Donato1, Flavia Molisso2, Filippo Terrasi3, Elda Russo Ermolli1

 
1Dipartimento di Scienze della Terra, dell’Ambiente e delle Risorse, Università di Napoli Federico II, Italy
2IAMC-CNR, Napoli, Italy
3CIRCE- INNOVA, Seconda Università di Napoli, Italyoppure
 
Journal of Coastal Conservation - Springer  
 
Abstract
A multi-proxy approach has been adopted to reconstruct the Holocene history of the St. Eufemia Plain (western Calabria, Italy) and to discern the influence that sea level rise and tectonics exerted in its evolution. Sedimentological, paleoecological and palynological data have been obtained from a 24-m long core, mostly made of pelitic back-barrier sediments, chronologically constrained by twelve AMS 14C dates. Radiocarbon ages of lagoon samples have been corrected by taking into account the influence of both the marine and hardwater effect on the reservoir age. The new data have been integrated with those of pre-existing stratigraphies in order to better characterize the overall sedimentary architecture of the plain. In the early Holocene (from ca. 8300 to ca. 6900 yr cal BP), eustasy largely prevailed on the tectonic uplift, causing coastline ingression and aggradation. From ca. 6900 to ca. 2800 yr cal BP, coastline progradation and aggradation were driven by high detrital inputs and slowdown of sea level rise, during a phase characterized by a general weak subsidence. From ca. 2800 to ca. 1400 yr cal BP, higher rates of subsidence favored the establishment of marsh and flooded alluvial plain environments in the back-barrier domain. After ca. 1400 yr cal BP, a substantial stability characterized the St. Eufemia Plain.
 
Key-words: AMS 14C ages, Reservoir effect, Ostracods, Pollen, Sedimentology, Stratigraphic architecture
 
Legenda figura.
Fig. 5 a) Geological cross section of the St. Eufemia Plain (see Fig. 1b for location) with position of the SL1 drilling site and of the intercepted boreholes (numbered from 1 to 14). Geometry of buried sedimentary bodies was reconstructed by integrating all available stratigraphical data collected in the plain. As subdivisions of detail were only possible at scattered sites, the adopted legend only distinguishes four broad sedimentary units within the Holocene. The main steps (1 to 4) in the evolution of the coastal setting are indicated by subsequent dotted lines. b) The diagram, plotted beside the environmental evolution at the SL1 site, shows the rates of apparent sedimentation (ARS) and relative sea level rise (RSL) in selected time intervals. RSL is obtained by balancing the sea level rise and the tectonic displacements measured in each interval. Intersection between ARS and RSL values defines the periods of retrogradation or progradation of the coastline