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The Sava Zone of the northern Dinarides is part of the Cenozoic Adria-Europe plate boundary. Here Late Cretaceous subduction of remnants of Meliata-Vardar oceanic lithosphere led to the formation of a suture, across which upper plate European-derived units of Tisza-Dacia were juxtaposed with Adria-derived units of the Dinarides. Late Cretaceous siliciclastic sediments, deposited on the Adriatic plate, were incorporated into an accretionary wedge that evolved during the initial stages of continent-continent collision. Structurally deeper parts of the exposed accretionary wedge underwent amphibolite-grade metamorphism. Grt-Pl-Ms-Bt thermobarometry and multiphase equilibria indicate temperatures between 550°C and 630°C and pressures between 5 and 7 kbar for this event. Peak metamorphic conditions were reached at around 65 Ma. Relatively slow cooling from peak metamorphic conditions throughout most of the Paleogene was possibly induced by hanging wall erosion in conjunction with southwest directed propagation of thrusting in the Dinarides. Accelerated cooling took place in Miocene times, when the Sava Zone underwent substantial extension that led to the exhumation of the metamorphosed units along a low-angle detachment. Footwall exhumation started under greenschist facies conditions and was associated with top-to-the-north tectonic transport, indicating exhumation from below European plate units. Extension postdates the emplacement of a 27 Ma old granitoid that underwent solid-state deformation under greenschist facies conditions. The 40Ar/39Ar sericite and zircon and apatite fission track ages from the footwall allow bracketing this extensional unroofing between 25 and 14 Ma. This extension is hence linked to Miocene rift-related subsidence in the Pannonian basin, which represents a back-arc basin formed due to subduction rollback in the Carpathians. [ABSTRACT FROM AUTHOR]

ABSTRACT Nappe refolding, back-thrusting and normal faulting frequently cause severe late-stage overprinting of the architecture of an orogen. A combined investigation of nappe stack polarity, kinematics of shearing and metamorphic gradients in the Western Alps develops criteria for distinguishing between these three modes of late-stage deformation. This distinction is a prerequisite for any retro-deformation necessary for understanding the main tectonic and metamorphic evolution of collisional orogens. In the case of the Western Alps overprint was by mega-scale nappe refolding in the Oligocene. This implies exhumation of the HP-rocks prior to postnappe folding, i.e. during nappe stacking and by foreland-directed ascent within a subduction channel. [ABSTRACT FROM AUTHOR]

In the original version of this article, one reference was incorrect. The following change was necessary: [ABSTRACT FROM AUTHOR]

Abstract: Thermochronological, structural and kinematic analyses demonstrate the influence of Late Paleozoic basement structures on the localization and evolution of the Rhine–Bresse Transfer Zone (RBTZ), a central segment of the European Cenozoic Rift System. Zircon and apatite fission track data indicate that the Paleozoic crystalline basement and its Permo-Triassic cover, exposed in the La Serre Horst, experienced a Middle Jurassic to Early Cretaceous heating event which was followed by two distinct periods of cooling. A first cooling event occurred in the Early Cretaceous and is probably related to thermal relaxation. A second one, started at around 38 Ma, is interpreted to reflect exhumation that was induced by fault reactivation along the Late Paleozoic Burgundy Trough System during Eocene–Oligocene rifting and the formation of the RBTZ. This fault reactivation resulted in a complex fault pattern and local stress field perturbations in the surroundings of the pre-existing horst structure. Substantial extension was achieved by ENE–WSW striking normal faults that trend highly oblique to the dominant strike of the Rhine and Bresse Graben rifts. Seismic reflection data show that these major normal faults are typically associated with extensional flexures and oriented parallel to pre-existing Late Paleozoic basement faults of the Burgundy Trough. Paleostress analyses yield overall NW–SE extension during the Eo-Oligocene, slightly oblique to the structural trend of the RBTZ, and additionally, local stress field perturbations induced by the reactivation of pre-existing faults. Reactivation of Paleozoic structures in the RBTZ is of extensional rather than of strike-slip character indicating that the RBTZ is forming a separate oblique graben segment within the European Cenozoic Rift System rather than a sinistral strike slip transform zone supposedly connecting Rhine and Bresse graben structures. [Copyright &y& Elsevier]