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Current tectonic models interpret the Hellenides as a unidirectional, SW-vergent orogenic belt. New (micro-)structural and amphibole chemistry analyses show, instead, that the exhumation of the Pelion Blueschist Nappe ( PBN) of the Internal Hellenides was achieved by retroward ( ENE)-directed ductile extrusion, which opposes the principal (proward) orogenic vergence. Retroward extrusion occurred between two sub-parallel, major ductile shear zones (Basal thrust and Upper detachment) with opposite shear senses, which operated simultaneously under blueschist- to greenschist-facies conditions during the late Eocene-Oligocene. Because the PBN is tectonically sandwiched between Pelagonian basement rocks, we suggest that the PBN protolith was accumulated during the Late Cretaceous in an incipient backarc basin developed above the NE-dipping subduction of the Pindos Ocean beneath the Pelagonian microcontinent. Subsequent Apulian-Pelagonian collision triggered basin inversion and the proward-dipping intracontinental subduction that caused the early/middle Eocene blueschist-facies metamorphism followed by the retroward extrusion of the PBN. [ABSTRACT FROM AUTHOR]

Palaeoseismological and archaeological analysis of a trench enabled us to estimate the Holocene slip rates on the East Helike Fault, flanking the south-western Gulf of Corinth. We recognized two major fault strands within the trench: the‘north fault’ controls a succession of three colluvial wedges and the deposition of a 2.7 m thick sedimentary sequence. The‘south fault’ controls the deposition of a 2.9-m thick brownish-red colluvium. Based on colluvial stratigraphy, radiocarbon dating of the sediments suggests that the slip rate wasc.0.3 mm yr−1 from 10 250 toc.1400 bp, when it increased dramatically toc.2.0 mm yr−1 after a strong earthquake event near 1400 bp. The faster slip rate evidently increased the sedimentation rate.Terra Nova, 17, 158–164, 2005 [ABSTRACT FROM AUTHOR]

Photomicrograph (cross‐polarized light) of a quartzofeldspathic mylonite from the ductile thrust zone that was formed during the emplacement of the Pelion Blueschist Nappe over the Pelagonian Zone (Hellenides, Greece). The photomicrograph illustrates rotated feldspar porphyroclasts embedded in a quartz‐rich ultramylonitic matrix indicating top‐to‐the‐NE (right) sense of shear. The length of the photomicrograph is 5.5 mm. (See the article by Gerogiannis and Xypolias, pp. 372–381) [ABSTRACT FROM AUTHOR]