Cenozoic extensional features in the geology of central mainland Greece

Abstract

The Hellenides of Greece have undergone a series of extensional deformation events from early Miocene to present time. Two of the fault systems that accommodate this deformation in central Greece are the Itea-Amfissa detachment and the Parnassos detachment. The Itea-Amfissa detachment is known to have been active during Middle Miocene (Langhian and Serravallian time) from dating of marine sediments within the syn-tectonic hanging wall basin. The Parnassos detachment is probably younger, based on the Lower Pliocene sediments deposited in the hanging wall, but stratigraphically lower sediments are undated. The North Giona fault extends east-west from near the northern end of the Itea-Amfissa detachment to near the northern end of the Parnassos detachment. This steeply north-dipping normal fault probably truncates the Itea-Amfissa detachment, and approaches the Parnassos detachment in an area where the topography is low and highly irregular, suggesting that it may connect to and absorb some of the motion along the Parnassos detachment. Structural mapping in this area between the North Giona fault and the Parnassos detachment demonstrates that the limestone and flysch of the Parnassos nappe are folded without significant faulting. Folds occur in two orientations; the northwest-oriented structures are older and are probably related to nappe emplacement; the younger, east-west trending folds are probably related to Late Cenozoic extension. The lack of through-going faults indicates that the North Giona fault and the Parnassos detachment do not connect. Structural relations also show that the Parnassos detachment is younger than the east-west trending fold structures within the field area, and also probably younger than the North Giona fault.