A palaeoseismological and geoarchaeological investigation of the Eliki fault, Gulf of Corinth, Greece

Palaeoseismological and morphotectonic analyses enable us to define a 400-m -wide actively deformed zone associated with the active Eliki normal fault, central Greece, bounded on the south by a second-order fault and on the no rth by a composite and prominent fault scarp. This scarp is further analyse d by trenching. Based on colluvium stratigraphy, displacement of distinct h orizons and deposition of sedimentary layers, three faulting events have be en identified along four fault strands affecting unconsolidated sediments i n the trench. The two younger events. with throws of 0.93 and 1.37 m, respe ctively, the third event, with a throw of 0.44 m, and the penultimate 373 B C event suggest a variable seismic history. The entire alluvial plain of the Kerynitis and Vouraikos rivers. which cros s the Eliki fault, has subsided at a rate of 1.4 mm/year. resulting in the burial of the Late Hellenistic-Roman occupation horizons under 3 m of fluvi al and colluvial sediments in places. Extension in the broader area is accommodated by the seismically active Eli ki and Egion faults. Structural and palaeoseismological analysis of those t wo faults indicates that they accommodate 1.5 mm/year, or about 10% of the geodetically estimated extension of up to 13 mm/year. (C) 2001 Elsevier Sci ence Ltd. All rights reserved.