Refinement of the Messinian APTS from sedimentary cycle patterns in the lacustrine Lava section (Servia Basin, NW Greece)

Abstract

A high-resolution cyclostratigraphy and magnetostratigraphy is presented for the Messinian lacustrine Lava section from the Servia Basin in NW Greece, constraining more precisely the absolute ages of magnetic polarity subchrons C3An.1n and C3An.2n. The section contains 15 distinct sedimentary cycles of alternating dark-and light-coloured marls, while the gamma-ray attenuation record reveals an additional five to six cycles. The cycles in the lower half of the section are on average 5.3 m thick, as opposed to the cycles in the upper part, which have an average thickness of 3.1 m. Palynological results define the lithological alternations in both the lower and upper cycles in terms of periodic changes in humidity, where the light marls represent the humid periods and the dark marls the relatively dry periods. Changes in cycle thickness and shifts in average gamma-ray values suggest a rather abrupt decrease in sedimentation rate at V60 m in the section. This is confirmed by the magnetostratigraphy, which recorded four reversals, which^given the biostratigraphic constraints from the Lava locality^could be correlated unambiguously to subchrons C3An.1n and C3An.2n of the geomagnetic polarity time scale. With this magnetostratigraphic time control, the average duration of the cycles can be calculated to be constant in the entire section, and similar to precession. The astronomical origin of the cycles is confirmed by the results of spectral analyses of gamma-ray and susceptibility time series. The sedimentary cycles in the upper part of the Lava section are unambiguously tuned to insolation using the typical clustering of the cycles that follows the eccentricity cycle. The filtered gamma-ray record centred at 41 kyr confirms the tuning in the upper part and allows tuning of the lower part. The tuning results in accurate ages for the sedimentary cycles and polarity reversals that confirm the astronomical tuning of [Krijgsman et al., Nature 400 (1999) 652^655], but define more precisely the astronomical polarity time scale. ß

Deformation of western Greece during Neogene clockwise rotation and collision with Apulia

“…1), which suggest that the dip-slip motion was preceded by a strike-slip activity. Lacustrine sediments of about 5 Ma old (Steenbrink et al 2000) in the footwall of the Aliakmon Fault show no evidence for synsedimentary SE-ward tilting, but at present have a SE tilt. This provides a maximum age for significant dip-slip activity of the Aliakmon fault zone of $5 Ma.…”

Progress in palynology of the Gelasian–Calabrian Stages in Europe: Ten messages

“…The investigations on marine cores covering the last climatic cycle off the Saharan coast has clearly demonstrated that during GCS glacial MIS it is dry in NW Africa (Hooghiemstra, 1989;Hooghiemstra et al, 2006). Ptolemais diagrams (Greece) show that cooler or drier periods were cyclically present very early on and well before the period considered here (Steenbrink et al, 2000(Steenbrink et al, , 2003.…”

“…When going further back in time, complex vegetation successions have also been observed, such as in the site of Ptolemais (Greece) (Fig. 1) during the Early Pliocene (Steenbrink et al, 2003) and at an earlier time in the Messinian, but less clearly (Steenbrink et al, 2000).…”

Late Cenozoic uplift of western Turkey: Improved dating of the Kula Quaternary volcanic field and numerical modelling of the Gediz River terrace staircase

“…Cenozoic lake basins in the Aegean region (e.g., Van Vugt et al, 1998Steenbrink et al, 1999Steenbrink et al, , 2000. In the absence of age control, taking account of the regional context Westaway et al (2004) inferred that its deposition ended around ∼3 Ma, being followed by a switch to fluvial incision accompanying a regional increase in uplift rates.…”