Holocene palaeoenvironmental changes in Agia Paraskevi prehistoric settlement, Lamia, Central Greece

Holocene palaeoenvironmental changes in the area of the prehistoric settlement of Megali Vrysi close to the village of Agia Paraskevi in Central Greece, 5 km east of Lamia City, were investigated. The area is situated in the low flat alluvial plain on the outskirts of Sperchios Valley that is bordered NNW to ENE by a rocky, hilly ridge of the Othrys Mountain foothills, 5.5 km away from the present coastline. The Megali Vrysi site is considered to be an important Mediterranean prehistoric commercial centre. Reconstruction of the palaeoenvironmental changes of the broader area adds new information concerning the general palaeogeographical setting of the settlement. Multidisciplinary research involved a detailed geomorphological survey combined with stratigraphical, palaeontological, and geophysical studies. The penetrated strata differentiated into 4 units from top to bottom. The first represents the archaeological strata. The second consists of the freshwater marshy sediments, while the third is the transition layer between the second and the deeper fourth group of marine – lagoonal sediments. The Holocene stratigraphy data was combined with the 14C-AMS dating results and showed a marine palaeoenvironment (∼ 5500 BC) gradually having shifted to a coastal – lagoonal one (∼3500 BC) and finally changed to a freshwater marshy environment (∼2500 BC). The comparison between ages and depths of the relative sea level points allowed the estimation of the sea level rise rate for the Agia Paraskevi area which is considerably lower than the one proposed for the Aegean Sea in the same time period. This considerable offset is attributed to the intensive tectonic uplift of the study area due to the tectonic deformation of the Sperchios Valley and this is probably why the prehistoric coastal settlement remained on the surface and unaffected from the sea transgression for more than 7000 yrs during Holocene.