Late Holocene palaeogeographic evolution of the Lihoura coastal plain, Pteleos Gulf, Central Greece

The present study aims to determine the Late Holocene palaeogeographic evolution of the coastal Lihoura plain located at the western part of Pteleos Gulf, in central-eastern Greece. The study area is a low-lying marsh, located at the mouth of an ephemeral stream. In order to determine the evolution of the plain, three cores (max. depth of 6 m) were drilled. Grain size analysis coupled with macro- and micro-palaeontological analyses were performed on sediment samples collected from the cores and six biosedimentary facies were identified corresponding to different depositional palaeoenvironments. The chronostratigraphy of the cores was established by 14C radiocarbon datings on three samples. Furthermore, detailed (at a scale 1:5000) geomorphological mapping was carried out, providing us with valuable information on the palaeogeographic evolution of the area. The results suggest that during the Mid-Holocene, the sea inundated the Lihoura Bay and created a transitional marine-brackish environment. The existence of an elongated (SW-NE) limestone peninsula along with the development of a sand bar shortly after 5027–5462 cal yrs BP, led to the formation of a protected lagoonal environment at the western part of the marshy plain, which at times was influenced by multiple terrestrial inputs induced by fluvial sediment supply. At the northern part of the marshy plain, a very recent high energy marine inundation event has been recorded in the sedimentary stratigraphy. Average rates of relative sea-level rise of 0.78 ± 0.24 mm/yr, 0.94 ± 0.24 mm/yr and 1.45 ± 0.77 mm/yr were estimated for the last 5244.5 ± 217.5 cal yrs BP, 5543 ± 196 cal yrs BP and 1901 ± 200 cal yrs BP respectively, which is in good agreement with previously published sea-level data for the broader area.