An integrated sedimentological, structural and geochemical study has been used to elucidate the tectono-sedimentary evolution of the Pindos Zone in the NW Peloponnese. The study area is interpreted as part of the Apulian passive margin which was bordered to the east by a small Neotethyan basin, the Pindos Ocean. The Pindos Zone is an elongate north-south trending imbricated terrane consisting of deep-water sedimentary rocks (the Pindos Group) that were deposited in the Pindos Ocean. The sedimentary rocks range in age from the Late Triassic to the Eocene. These sediments were deposited on a volcanic substratum that is sparsely preserved as blocks within melange at the base of Pindos thrust sheets. Cursory analysis suggests that the extrusive igneous rocks exhibit geochemical signatures comparable with island arch tholeite (IAT). However, further geochemical study indicates that parental members of the suites represent transitional within plate basalt (WPB) to mid-ocean ridge basalt (MORB) lava. The recognition of spatial and temporal facies trends within the over lying sedimentary rocks, augmented by laboratory analysis, allows the sedimentary evolution of the passive margin to be documented from rifting to final suturing. Earliest recorded sediments consist of Late Triassic sandstones, derived mainly from a metamorphic source terrane, intercalated with <i>Halobia</i>-bearing limestones. Thereafter, a proximal to distal facies distinction is recognised in the sedimentary sequence. Late Triassic to Liassic facies consist of coarse calcirudites and nodular limestones in the west, while to the east, distal calciturbidite, micrite and chert facies are present. During Aalenian times, sedimentation underwent a fundamental change from calcareous to siliceous deposition, via an argillaceous interval. The Middle and Late Jurassic is dominated by radiolarian-rich, ribbon-bedded, cherts. The passive margin period was interrupted in the Late Jurassic by a short period of localised faulting and volcanic activity.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:649458 |
| Date | January 1992 |
| Creators | Degnan, Paul J. |
| Publisher | University of Edinburgh |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/1842/13608 |
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