Geomorphology and evolution of the region between Lapa and Eleotopos, northwestern Peloponnesus (Greece)

Abstract

The northwestern part of Peloponnesus (Greece) between the villages of Lapa and Eleotopos (37°56', 21° 14', 38°05', 21°30') is characterized by a series of morphological units: a) a mountain front, b) an ancient piedmont passing seawards in to a wide terraced area, c) a coastal plain with marshes. Geological and geomorphological analyses of the area suggest the following evolution. Before or during isotopic stage 7, and as a consequence of an extensional tectonic pattern, a sinking of the Ionian zone flysch was followed by a sea transgression and by the creation of a wide bay near the Skolis mountain front. In this bay, a marine-lagoonal succession was deposited during isotopic stage 5. After isotopic stage 5, a regression occurred and marine deposits were covered by alluvial and colluvial sediments which created a wide "pediment" and alluvial fans. The extensional tectonics dislocated these sediments, showing uplift at the mountain front and lowering downward in the valley. The last lowering is represented by alluvial deposits in the coastal plain. These deposits were incised and terraced (New Vouprassio terrace) due to a new local tectonic action. This new plain is Holocene in age. Of special interest is the post-Tyrrhenian fault scarp which dislocates the Varda terrace from the Vouprassio terrace.