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The relationship between subduction dynamics and crustal deformation in the Mediterranean region has been recently studied using three-dimensional (3D) models. Such models require, however, detailed information concerning the past geological evolution. We use stratigraphic, petrologic, metamorphic, structural, paleomagnetic and magmatic data to build new kinematic reconstructions of the eastern Mediterranean region since the late Cretaceous using the principle of non-rigid domains. The motions of the 56 deforming domains defined in this work are calculated based on published paleomagnetic rotations, the directions and amounts of displacement on crustal-scale shear zones and the burial and exhumation histories of the main metamorphic units. Extracted from these reconstructions, paleotectonic maps and lithospheric-scale cross-sections illustrate that the present-day subduction zone has been continuously retreating southward since the late Cretaceous and has accreted several small continental domains in the process. We find evidence for two back-arc-related extensional events: (1) slow extension along the Balkans and the Pontides in the late Cretaceous while the trench was long and linear and (2) faster extension in the Rhodope-Aegean-west Anatolian region since the Eocene–Oligocene. Rapid rotation of the Hellenides between 15 and 8 Ma probably indicates a slab tearing event below western Anatolia that could have further accelerated this extensional kinematics. Spatial distribution and the geochemical signature of magmatic centers integrated in these reconstructions allow us to trace mantle-related processes revealing the deep dynamics that controls both the magma genesis and the crustal deformation. [ABSTRACT FROM AUTHOR]

Abstract: Geological data suggest that, after a period of oceanic lithosphere subduction, about 170km of continental lithosphere were subducted under the Northern Apennines since about 23Myear at rates of ca. 1cm/year, whereas more than 700km of Mesozoic oceanic lithosphere (Ionian lithosphere) have been subducted under the Calabrian arc at rates of about 3cm/year. However, a well-developed Wadati-Benioff zone can be only recognised below the Calabrian arc down to depths of 450–500km, whereas intermediate-depth seismicity reaches maximum depths of about 90km under the Northern Apennines. We model the thermal state of these two subduction zones and apply temperature-dependent non-linear rheological laws to evaluate the down-dip extent of brittle regions in the two subduction zones. We show that differences in subduction rate and in slab composition (continental vs. oceanic) produce a far deeper (down to 290–380km) brittle field in the colder Calabrian slab than in the warmer Northern Apenninic slab (70–120km), thus explaining differences in the maximum depth of seismicity in both regions. Concerning deep earthquakes in the Calabrian subduction zone, models predict that metastable olivine persists down to depths of 430km. This could possibly explain the maximum depth of earthquakes in the area. The small extent of the metastable olivine wedge produces a small density anomaly that cannot explain the pervasive down-dip compression observed in the Ionian slab. [Copyright &y& Elsevier]