## 2 Geological Setting  
The study area is located in southern Poland, in the eastern part of the Carpathian Foredeep. Similarly to other young foreland basins, the Carpathian Foredeep is filled with Miocene clastic sediments of thickness up to about 3000 m [12]. Formation of the Carpathian Foredeep is related to evolution of the Outer Carpathian orogenic belt in the Miocene [13,14]. The southern, tectonic boundary of the Foredeep is defined by the front of Outer Carpathian nappes, which were thrusted over the Miocene sedimentary fill of the foreland basin [15, 16, 17], whereas the northern boundary is erosional [18]. The basement of the Foredeep is the epi-Variscan platform and/or its Permian-Mesozoic sedimentary cover [12, 18, 19, 20]. Generally, the Miocene sedimentary fill of the Foredeep was developed along the front of the Carpathian orogen, but some formations were involved in the fold-and-thrust belt structure and now form the outermost Carpathian tectonic units. Moreover, some units were even thrusted over the Carpathian nappes, whereas the others underlie the Carpathian Overthrust as autochthonous formations [21]. The Foredeep was divided into the two zones [22]. The first zone of the Inner (older) Foredeep includes Miocene sediments resting either beneath the Carpathian nappes in an unchanged (autochthonous) position or forming allochthonous structures along the front of the Flysch Carpathians, determined as the Stebnik and the Borislav-Pokuttya units [15,19]. The second zone of the Inner Foredeep comprises Upper Badenian/Sarmatian sediments [13], which were partly included into the Carpathian orogen and went on to build the current Zglobice Unit [23, 24, 25, 26]. Both zones are filled with Miocene sediments, however, the most important hydrocarbon reservoirs are hosted in the autochthonous series of the outer part of the Foredeep, whose thickness reaches up to 3500 m in the Wielkie Oczy Graben [20]. The Miocene formations of the Carpathian Foredeep comprise: (i) Lower Badenian Sub-evaporate Series, (ii) Middle Badenian Evaporate Series and (iii) Upper Badenian/Sarmatian Supra-evaporate Series [20]. The oldest sediments belong to the Baranow Beds, represented mostly by green or greyish-green clayey shales interbedded with marls and glauconitic sandstones. In the areas of Cetynia, Lubaczow and Dzikow, thickness of this sandy-clayey part of the Baranow Beds reaches locally up to 70 m, but the average thickness only extends to several meters and porosity varies from 5 to 25% [20]. The overlying Evaporate Series is represented in the eastern Foredeep by the Krzyzanowice Formation with thicknesses from 0 to 60 m. These are mostly anhydrites, gypsums and both the primary and the epigenetic limestones. Porosity of these carbonates is only about 2-3% and permeability varies from 0.01 to 1.05 mD, although secondary porosity may reach a dozen per cent [20]. The Supra-evaporate Series rests upon the older sediments or directly on the basement rocks. Significant thickness of these clayey-sandy deposits, up to 2500 m, results from Late Badenian and Sarmatian subsidence of the basin floor. Usually, these sediments are named the Machow Formation and include the Spiralis-Pecten Beds and the Krakowiec Beds. However, in the Dzikow area, a limestone succession was encountered, in which two members were distinguished: the lower micritic limestones and the upper silty limestones. Porosity of these carbonates varies from 4.32 to 16.07% [20]. Geometry of the Carpathian Foredeep is not uniform due to rejuvenation of faults within the Teisseyre-Tornquist Zone, which took place in the Miocene. The central part of the Foredeep is cut by a broad zone of compressional deformations, well-visible within the Miocene formations. However, in the eastern part, different geometry is observed as a complicated system of faults generated during the Miocene extension combined with the regional compression forced by continental collision.