Jurassic geodynamics of ridges within the Outer Carpathian realm in Poland

The complex Mesozoic tectonics of the Outer Carpathians produced series of ridges separating deep water basins. The Penninic-Pieniny Ocean, which originated during the Early Jurassic, was divided into the northwestern and southeastern basins by the mid-oceanic Czorsztyn Ridge. This ridge became well pronounced during the Middle Jurassic. The occurrence of mafic (basalt) intrusions at the eastern termination of the Czorsztyn Ridge in the Novoselica Klippen (Lashkevitsch et al. 1995; Golonka et al. 2004; Krobicki et al. 2005) seems to support the thermal origin of the ridge related to sea-floor spreading. During Jurassic - Early Cretaceous time the Czorsztyn Ridge was submerged and did not supply clastic material into the Pieniny and Magura Basins. This observation provides an argument against the origin of the ridge as the rifted-away fragment of the European Platform. The Jurassic - Early Cretaceous Silesian Ridge originated as a result of the fragmentation of the European Platform in this area (Golonka et al. 2003, 2004). The proto-Silesian Basin was formed during the synrift process with a strong strike-slip component. The complex system of rotated blocks was borne. The emerged fragment of these blocks supplied material to the basin. The opening of the basin is related to the propagation of the Atlantic rift system (Golonka et al. 2003). The Silesian Ridge separated the proto-Silesian Basin from the Alpine Tethys. The Eastern Carpathian (Sinaia or "black flysch") as well as to the Southern Carpathian Severin zone (Sandulescu 1988) are somehow related to this proto-Silesian basin. The direct connection is obscured however by the remnants of the Transilvanian Ocean in the area of the eastern end of Pieniny Klippen Belt Basin. In this area existed a junction of the different basinal units - Alpine Tethys, Transilvanian Ocean and Outer Carpathian Basin. The Bucovino-Getic Microplate (Golonka et al. 2003) constitutes a fragment of the East European Platform. It includes Precambrian, Early Palaeozoic (Caledonian) granites and metamorphic rocks, Late Palaeozoic (Variscan) metamorphic rocks as well as the late Palaeozoic and Mesozoic sedimentary cover. The connection of this Bucovino-Getic microplate with the Silesian Ridge is uncertain because of transform faults related to the Jurassic opening of Alpine Tethys.