GEOLOGY OF THE KOUTSONGILA RIDGE AND THE ROMAN CEMETERY OF KENCHREAI, EASTERN KORINTHIA, GREECE

The Roman cemetery of Kenchreai, which consists of 54 known burial sites, is located on a ridge overlooking the Saronic Gulf and the seaward approach to the eastern Korinthia. The ridge comprises Plio-Pleistocene marl, sandstone, and conglomerate, and several valley fills of various age. Landscape change has been rapid and significant due to co-seismic subsidence, drainage reconfiguration and coastal erosion. Currently, tombs are eroding from the coastal cliff and a Roman villa, seawall (?) and road are submerged in the nearshore. Earthquakes in ca. 400 and 1928 produced a combined subsidence of 1.25m, and archaeological remains, wave-cut notches, and submerged beachrock suggest that the Roman coastline was situated within 20m of the present shoreline.

Roman builders took advantage of the physical properties of the local geology through burial location and construction. The majority of chamber tombs (26 of 29) lie within a valley fill of sandy mudstone with conglomeratic horizons. This homogeneous unit is best suited for rock-cut tomb construction; significantly, the tombs follow the strike of this unit rather than the contour of the ridge. Additionally, a caliche of variable thickness exists throughout the area. The springing of the vault in each tomb conforms to the base of the caliche profile regardless of local depth, thus making the tomb ceilings resistant to collapse. Our landscape reconstructions indicate that the tombs, which were located on a slope above a high coastal cliff, were visible to maritime traffic approaching the city and thus occupied a prominent position in the civic landscape.