eEarth www.electronic-earth.net 1815-381X 1815-3828 4 1 2009 10.5194/ee-4-23-2009 http://www.electronic-earth.net/4/23/2009/ http://www.electronic-earth.net/4/23/2009/ee-4-23-2009.html http://www.electronic-earth.net/4/23/2009/ee-4-23-2009.pdf 23 29 2009-07-13 Holocene evolution and sedimentation rate of Alikes Lagoon, Zakynthos island, Western Greece: preliminary results P. Avramidis pavramid@teimes.gr N. Kontopoulos Technological Educational Institute of Mesolonghi, Department of Aquaculture and Fisheries Management, 30200 Mesolonghi, Greece University of Patras, Department of Geology, 26500 Patras, Greece In the present study we present preliminary results from Alikes lagoon in Zakynthos island, an area that is one of the most seismically active regions of Greece. In order to estimate – interpret the Holocene evolution of the area and to reconstruct the palaeoenvironmental changes, we based on data derived from a 21 m sediment core. Sediment types, structure, colour, as well as contact depths and bed characteristics were recorded in the field. Standarised sedimentological analysis was carried out, on 46 samples including grain size analysis, calculation of moment measures, and micro- and molluscan fossils of 17 selected samples. Moreover, radiocarbon age determinations have been made on individual <i>Cardium</i> shells from two horizons and whole – core Magnetic Susceptibility (MS) measurements were taken. The interpretation of depositional environments suggests a coastal environment (restricted-shallow) with reduced salinity such as a lagoon margin and in a tidal flat and/or marsh particularly. The maximum age of the studied sediments is about 8500 BP. The rate of sedimentation between 8280 BP while 5590 BP was 5.3 mm/yr and between 5590 BP and modern times is on the order of 1.03 mm/yr. These sedimentation rates results are similar to other coastal areas of western Greece. Aubouin, J. and Dercourt, J.: Zone préapulienne, zone ionienne et zone du Gavrovo en Péloponnèse occidental, Bull. Soc. Gèol. France, 7, t. IV, 785–794, Paris, 1962. Avramidis, P., Bouzos, D., Antoniou, V., and Kontopoulos, N.: Application of grain size trend analysis and spatio-temporal changes of sedimentation, as a tool for lagoon management. Case study: the Kotychi lagoon (western Greece), Geological Carpathica, 59, 3, 261–268, 2008. Bird, E.: Coastline changes. A global review, J Wiley and Sons, Chichester, 219~pp., 1985. Folk, R. I.: Petrology of sedimentary rocks, Hamphill, Austin, Texas, 1–182, 1974. Kelletat, A.: Holocene sea level curve for the eastern Mediterranean from multiple indicators, Zeitschrift für Geomorphologie N.F. Supplement 137, 1–9, 2005. Kontopoulos, N. and Avramidis, P.: A late Holocene record of environmental changes from the Aliki lagoon, Egion, North Peloponnesus, Greece, Quatern. Int., 111, 75–90, 2003. Kontopoulos, N. and Koutsios, A.: A late Holocene record of environmental changes from Kotihi lagoon, Elis Northwest Peloponnesus, Greece, Quatern. Int., doi:10.1016/j.quint.2008.10001, in press, 2009. Kraft, J. C., Rapp, G. (Rip), Gifford, J. A., and Aschenbrenner, S. E.: Coastal change and archaeological settings in Elis, The American School of Classical Studies at Athens, Hesperia, 74/I, 1–39, 2005. Lekkas, E.: Neotectonic map of Greece, Zakynthos – Volime, scale 1:50000, University of Athens, 116 pp., 1993. Piper, D. J. W. and Panagos, A. G.: Growth patterns of the Acheloos and Evinos deltas, western Greece, Sediment. Geol., 28, 2, 111–132, 1981. Scott, D. B. Piper, D. J. W., and Panagos A. G.: Recent salt march and intertidal mudflat foraminifera from the western coast of Greece, Riv. Ital. Paleont., 85, 1, 243–266, 1979. Underhill, J.: Triassic evaporites and Plio-Quaternary diapirism in western Greece, J. Geol. Soc. London, 145, 269–282, 1988. Vött, A.: Relative sea level changes and regional tectonic evolution of seven coastal areas in NW Greece since the mid-Holocene, Quaternary Sci. Rev., 26, 894–919, 2007. Zelilidis, A., Kontopoulos, N, Avramidis, P., and Piper D. J. W.: Tectonic and sedimentological evolution of the Pliocene – Quaternary basins of Zakynthos, Greece: Case study of the transition from compressional to extensional tectonics, Basin Res., 10(4), 393-408, 1998.