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The western part of the Polish Outer Carpathians is built up from the thrust, imbricated Upper Jurassic-Neogene flysch deposits. The following Outer Carpathian nappes have been distinguished: Magura Nappe, Fore-Magura group of nappes, Silesian, Subsilesian and Skole nappes. Interpretation of seismic and magnetotelluric survey from the region South of Wadowice, allows observation of relationship between basement and flysch nappes in the Outer Carpathians. It also allows identification of dislocation cutting both flysch nappes and their basement. All the Outer Carpathian nappes are thrust over the southern part of the North European Platform. The platform basement is composed of older Precambrian metamorphic rocks belonging to the Bruno-Vistulicum terrane. Sedimentary cover consists of Paleozoic, Mesozoic and Neogene sequences. The characteristic features of this boundary are horsts and troughs of general direction NW-SE, turning W-E. Faults cutting only the consolidated basement and the Paleozoic cover were formed during the Hercynian Orogeny in the Carboniferous and the Early Permian. Most of the older normal faults were covered by allochtonous flysch nappes forming thus the blind faults. During the last stage of the geodynamic development the Carpathians thrust sheets moved towards their present position. Displacement of the Carpathians northwards is related to development of dextral strike-slip faults of N-S direction. The orientation of this strike-slip fault zones zone more or less coincides with the surface position of the major faults perpendicular to the strike of the Outer Carpathian thrustsheets. The huge fault cuts formations from the Paleozoic basement through the flysch allochton between the boreholes in Sucha Beskidzka area. The displacement of nappes of the Carpathian overthrust and diapiric extrusion of plastic formations of the lower flysch units occurred along this fault.

The authors interpret the structure of the Central Carpathian-North European plates suture zone in Poland, where three main Carpathian tectonic units: the Central Carpathian, Pieniny Klippen Belt (PKB) and Outer Carpathian are present. In general, the PKB follows this zone. Several deep boreholes were drilled in this region and the seismic lines were tied to borehole data and geological maps. The Polish PKB belongs to the complex geological structure stretching from Vienna in Austria to Romania. The rocks included in the PKB tectonic components were deposited within the paleogeographic realm known as the Alpine Tethys, mainly during the Jurassic-Early Cretaceous times. Both strike-slip and thrust components occur within the Polish section of the PKB. The strongly tectonized, few kilometer wide PKB zone is limited by a flower structure marked by two major faults, linked to the strike-slip zone. These faults reach the North European Platform (part of the North European Plate). The flysch sequences, arranged into a series of north-vergent thrust-sheets, constitute the main component of the PKB in the survey zone. They contain olistoliths, which are mainly Jurassic-Early Cretaceous in age. The PKB tectonic components of different age, strike-slip, thrust as well as toe-thrusts and olistostromes are mixed together, giving the present-day mélange character of this belt, where individual units are hard to distinguish. Two olistostrome belts (mélange units) exist within the PKB structure. The seismic lines show the Central Carpathian Paleogene rocks covering the Paleozoic Central Carpathian Basement south of the PKB. The Subtatric covers the High-Tatric autochthonic and allochthone rocks. The Central Carpathian Plate is thrust over the North European Platform in the Podhale region. The allochthonous Outer Carpathians consist of several nappes (thrust-sheets) verging northward. They are thrust over each other and over the North European Platform which dips gently southward.