Late Holocene emergence in Calabria, Italy

• Published in: Marine geology 1997-09, Vol.141 (1), p.61-70
• Main Authors: Pirazzoli, P.A., Mastronuzzi, G., Saliège, J.F., Sansò, P.
• Format: Article
• Language: English
• Subjects: Calabria; Holocene; isostatic modelling; Marine; sea level; shoreline; tectonics
• ISSN: 0025-3227; 1872-6151
• DOI: 10.1016/S0025-3227(97)00057-1

A field survey along the coasts of Calabria has found little evidence of Holocene emergence, the greatest being no more than 1.0–1.5 m in elevation. A former shoreline (a thick crust of calcareous algae in growth position at about + 0.6 m, capping an elevated beachrock slab) was dated 2990 ± 60 yr B.P. This emergence is recent, if compared to the time of the Climatic Optimum, and relatively slight, if Late Pleistocene uplift rates, which in some cases exceed 1 mm/yr, are considered. This apparent discrepancy can be explained by taking into account glacio- and hydroisostatic effects of the last glaciation, which have produced subsidence at decreasing rates during the late Holocene in a wide area around the former Scandinavian ice sheet which includes most of the Mediterranean. According to isostatic modelling, the average subsidence rate during the last 6000-5000 years was between 0.4 and 1 mm/yr near the coasts of Calabria. If global sea-level changes can be neglected, it is only when the subsidence rate of glaciohydro-isostatic origin became slower than the local uplift that emergence at a slower rate than that of the tectonic uplift trend could have begun. Such emergence is therefore a recent phenomenon, in the Holocene, and its rate is still much slower than that of tectonic uplift predominating in Calabria over a longer time scale.