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During the migration of the back arc extension from central to western Greece the Corinth and Patras grabens are being formed. Orthogonal opening of these graben zones is accomplished by WNW listric normal faults and NNE transfer faults which produce an along-axis fragmentation. The listric faults show an increase in the dip of the fault plane westwards as well as a decrease in the maximum extension rate from 50% to the east in the Corinth graben, to 10% to the west in the Patras graben. Similarly, towards the west, P l i e u a t e r n a r y deposits become thinner whereas Pliocene sediments thin-out indicating a westward rift propagation. another orthogonal fault system consisting of NNW and ENE normal faults. These faults have been formed during general uplift behind the orogenic front which has been migrating from western Greece to the Ionian islands. T h e ENE-trending Rio graben which belongs to his orthogonal system connects the Patras graben to the Corinth graben and has subsequently been active as a transfer fault between them.Plio-Quaternary geodynamic processes in central continental Greece are quite similar to those earlier processes observed in the central Aegean region which reflect the initial stage of continental break-up behind a migrating orogenic front.As the back arc extension migrates westwards it is interacting or is being superimposed above

An exhumation model comprising forward and backward thrusting and late orogenic collapse is proposed in order to explain the kinematics of the tectonic windows in the south Peloponnesus. The model is based on mapping, mesoscopic structural data and strain analysis. Syn-compressional thickening took place throughout the Oligocene and Early Miocene which includes the subduction of the Pindos Ocean at the western margin of the Pelagonian microcontinent and the intracontinental subduction of the Phyllite± Quartzite and the Plattenkalk series. The latter subduction was associated with blueschist metamorphism, westward-directed ductile thrusting, and folding. The exhumation history of the deeper parts of the orogen began at the Oligocene±Miocene boundary with the progressive entrance of the low-density crust and the Plattenkalk carbonates in the subduction zone. Increased buoyancy caused: (a) the initiation of the Phyllite±Quartzite series extrusion; (b) vertical coaxial stretching; and (c) the evolution of two pop-up structures, i.e. the Parnon and Taygetos anticlines. This syn-compressional exhumation was taking place in the lower Miocene with decreasing rates from 7 to 1.5 mm/year. The change in the local stress field from compression to extension began in the middle Miocene with the formation of hinterland-dipping normal faults. The exhumation/denudation rate caused by the footwall uplift along these faults does not exceed 0.2 mm/year.

A new subtype of Gilbert‐type fan deltas, ‘the trapezoidal fan delta’, characterized by the absence of bottomset deposits, is recognized in the south‐western active margins of the Corinth rift in central Greece. They are formed adjacent to master extensional listric faults and developed by progradation either onto a subaqueous basin escarpment or across a subaerial platform where alluvial fans have accumulated. Simultaneously with master fault activity, displacements on counter faults along intrabasinal basement highs produced fan delta foreset deposits. Furthermore, footwall imbrication and uplift along the listric faults, as well as transfer fault displacement, have strongly influenced the pattern of fan delta sedimentation.

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