1 - "Lower Unit", comprising two subunits: at the base the "Agoriani Mélange", with blocks of ocean- and continent-derived rocks, among which MORB and IAT ...
Triassic and Jurassic cherts linked to the MOR basalts in the Othris area (...
1 of 1
http://www.cprm.gov.br/33IGC/1345190.html
Home Search Abstracts Author Index
HPF-01 General contributions to paleontology and historical geology Triassic and Jurassic cherts linked to the MOR basalts in the Othris area (Greece)
Symposia Programmes Sponsors Help
Marco Chiari, CNR-IGG (Italy) Valerio Bortolotti, University of Florence (Italy) Marta Marcucci, University of Florence (Italy) Adonis Photiades, Institute of Geology and Mineral Exploration (IGME) (Greece) Gianfranco Principi, University of Florence (Italy) Emilio Saccani, Università di Ferrara (Italy)
In the Othris region, Greece, at the top of the Pelagonian sedimentary series, three ophiolitic units crop out, in tectonic contact: 1 - "Lower Unit", comprising two subunits: at the base the "Agoriani Mélange", with blocks of oceanand continent-derived rocks, among which MORB and IAT volcanics; at the top the "Fourca Subunit", consisting of altered pillow lavas topped by red cherts; 2 - "Middle Unit", composed of serpentinized harzburgites with dunite bodies and amphibolite slivers at the base; 3 ? "Upper Unit", consisting of plagioclase lherzolites. The whole thrust pile system is unconformably covered by Upper Cretaceous limestones, a Paleocene flysch and Oligocene-Miocene molasse. We collected (1999-2004) chert samples for radiolarian biostratigraphy and basalts for geochemistry analyses in the Lower Unit in the Fourca Subunit and in blocks included in the underlying Agoriani Mélange. The preliminary radiolarian biostratigraphical data and geochemical results point to a Triassic (probably late) age for the MOR basalts. They indicate, as previously found in other Dinaric-Hellenic areas (Mirdita Zone, Albania; Pindos, Argolis, Greece, etc.), the presence of a Triassic Tethyan ocean basin. No biostratigraphical age we have obtained so far, related to the IAT rocks of the mélange which, however, all along the Dinaric-Hellenic chain begin during the Middle Jurassic.
CD-ROM Produced by X-CD Technologies
30/9/2009 11:11 πμ
