Introduction and Explanatory Notes

Structure, tectonic processes and deformation of the South Aegean Sea

“…The current study cautiously infers that Units 1, 2, 4 and 5 represent the Plio-Quaternary sediments overlying an erosional surface which corresponds to the Messinian Margin Erosion Surface (Roveri et al, 2014) at the basin's margin, while in the basin they have been deposited above the Messinian evaporites (Unit 6). The seismic characteristics of the surface and of the internal reflectors of Unit 6, as mentioned in Section 4.1.5.1. coincides very well with the results of DSDP Hole 378, in the Cretan Basin (Hsu et al, 1978). If this assumption is correct, then Unit 6 constitutes the selenite facies similar to the onshore Primary Lower Gypsum deposits (Lugli et al, 2010).…”

“…The seismic character and the irregular morphology of this interface along with the seismic character of Unit 6, are good arguments to suggest that it represents the Messinian marker as observed by below Milos Basin. Furthermore, this is in good agreement with the results of the Deep Sea Drilling Project (DSDP), Hole 378, in the Cretan Basin (Hsu et al, 1978). The reflective Unit 5 which overlies the Unit 6, may correspond stratigraphically to the Zanclean -Early Pliocene marls of the Trubi or Argille Azzure Formations (Roveri et al, 1998(Roveri et al, , 2008(Roveri et al, , 2014.…”

“…Unit B is unconformably resting on unit C showing strong and continuous reflectors, such as those in subunit A2, although its reflectors display higher amplitude. The unconformity between Unit A and Unit B coincides with the Pliocene/Quaternary boundary of the drilling results of Site 378 (Hsu et al, 1978), indicating that Unit B is mainly of Pliocene age, while Unit A is assumed to be of Quaternary age . According to , the lowermost parts of unit B were deposited as a basin filling facies during and after the formation of the basins.…”

“…It indicates a major change in the tectonic regime with rearrangement and faulting of the Pliocene basins, onset of local subsidence and basin inversion . By comparison with the aforementioned data, it is proposed here that Unconformity U3 is equivalent to the Early Quaternary unconformity observed in DSDP hole The basin evolution model presented above builds on older studies by Piper and Perissoratis (see Hsu et al, 1978 and in the area extending to the East of Santorini. They have observed a major change of the tectonic regime in the boundary between Pliocene and Quaternary that led from E-W normal faulting to NE strike-slip faulting.…”

“…The available data from SASZ do not allow a precise determination of the age of Unconformity U3. Chronological constraints of the post-Messinian infill of sedimentary basins in the Aegean Sea derives (i) either from the interpretation of low sea level prograding sequences and clinoforms or (ii) by comparison with the results of the Deep-Sea Drilling Project (DSDP) hole 378 in the Cretan Sea (Hsu et al, 1978). The latter penetrated 343.5 m below the seafloor and revealed two major unconformities: the top of the Messinian evaporites at roughly 305-310 m bsf and a younger one at roughly 130m bsf of an Early Quaternary approximate age (also see Tsampouraki-Kraounaki and Sakellariou, 2018, Figure 6, for a short section of a recent seismic profile through the 378 hole).…”