The recent discovery of a post-Roman-aged marine calcarenite terrace, at an altitude of 7 to 8 m at the ancient harbor of Akhziv, supports the hypothesis of oscillatory tectonic movements along the coastline of Israel during the late Holocene. The marine to estuarine origin of this terrace is indicated by the presence within it of a biocoenosic, sea-marginal to estuarine, assemblage of well-preserved molluscs consisting of taxa tolerating brackish-water, together with a few fresh-water specimens. The transgressive marine sediments onlap and overlie a 2700-yr-old middle Iron Age (Phoenician) tomb, which was built on a dark clay layer, containing a middle Bronze HB (3750 yr B.P.) settlement. In post-Roman times the coastal zone at this site, both east and west of the present coastline, was first subjected to tectonic subsidence of a few meters, and was then tectonically uplifted to its present altitude.
