A new subdivision of the pre-Jurassic Pelagonian Units in central Evia
island is proposed these units are represented by syn- and post rift
sequences, separated by a volcano-sedimentary episode.
The syn-rift sequences comprise Permian siliciclastic sediments in
Verrucano tectofacies, (Ano Mavropoulon Formation) and a small carbonate
platform (Zigos Limestones) developed from the Permian to the Middle
Anisian. The Ano Mavropoulon Fro, is subdivided into three members:
the lower member (Permian s.l.) lying on the basement and characterised
by medium-coarse elastic terrigenous sedimentation
the middle member (Late Permian) Koprises limestones, made up of
shallow-water limestones;
the upper member (Latest Permian-Early Triassic) comprising elastic
terrigenous and minor reworked carbonate sediments.
A regional unconformity (earliest Triassic) separates the Zigos Lm. from
the top of the Ano Mavropoulon Fm. The peritidal carbonates belonging to
the Zigos Lm, have been subdivided into three lithofacies ranging in age
from Spathian to Pelsonian (late Early Triassic to Middle Anisian).
The volcanic episode is well constrained in all the Pelagonian domain.
In central Evia, it has been dated from Middle Anisian to Early Carnian.
The sub-alkaline to alkaline basalts comprised in the
volcano-sedimentary sequence (Volcano-sedimentary Complex) have a
within-plate affinity. The volcanism occurs between the syn-rift and
post-rift stages, and it is probably not linked to the passive margin
evolution proper.
The post-rift sequences are represented by the onset of the Pelagonian
platform aggradation (''Pantokrator'' Carnian to Middle-Late?
Jurassic)
The northern passive margin sequence of Pelagonia (palaeogeographic
sense) is interpreted as related to the Maliak ocean opening during the
Early Mesozoic.