Here the Cretaceous and Paleogene flysh of the Duklya-Chornohora, Burkut, Magura, Marmarosh and Pieniny covers was studied that in the north-western sector of the Ukrainian Carpathians near the border of Poland and Slovakia (Lemkivsky segment) distinguish themselves by very inclined thrusts. Spatially the given tectonic units are within the limits of so called hydrothermal field unfavourable as a whole, as to the presence of hydrocarbons on a large scale here. But there were distinguished small plots with prevalence of hydrocarbons in the gas composition. Prospects of the potential for gas presence in the region should be connected with the areas that spatially gravitate towards Transcarpathian deep. Studied area consists of several tectonic units of the first order. These are covers located farther south-west of Krosno cover: Duklya-Chornohora, Burkut (Porkulets), Magura, Marmarosh and Pieniny covers, in the south-west the studied terrane is limited by the Transcarpathian deep, and farther west – by the state border of Ukraine and Slovakia, in the south-east – by the Rika Rriver, in the north-east – by the zone of joining of Duklya-Chornohora and Krosno covers. Prospects of the potential for oil end gas presence in the given area, as in the Folded Carpathians on the whole, should be determined by the complex of all accompanying parameters: structural, collecting and covering, hadrochemical and geochemical. For the given area of the Carpathians the geochemical factor is the most important.

In the paper a model of the formation of the folded-covering-block structure of the Carpathians at a time interval that envelops Late-Hercynian and Alpine events is substantiated. Moreover, this concerns the Outer Carpathians, but the whole Carpathians arch was characterized without going into details, a critical estimate is expressed for application of such terms as terrains, accretion prism, suture, subduction and Transcarpathian fault. It is shown that formation of the Carpathians occurred through several stages under the influence of different-directed, manly horizontal, movements, as a result of which was destruction of early formed Hercynian continental crust, laying of geosynclinals troughs, formation and further transformation of the basement of the Flysch Carpathians, its collision with Eurasian continental edge, underling of the latter under flysh complex. After completion of these processes mainly vertical movements took place that lineally formed the structure of the Carpathians as folded-covering-block one. As a result of the last event (Pliocene-Pleistocene), a differential development of intensive fracturing occurred with the influx of hydrocarbons and filling traps formed up.

We have studied the Cretaceous and Paleogene flysch of the Duklya-Chornohora, Burkut, Rakhiv, Marmarosh and Pieniny covers that in the south-eastern sector of the Ukrainian Carpathians near the Romanian border (Hutsulian segment) distinguish themselves by very inclined overthrust. Spatially the given tectonic units are in so-called hydrothermal fluid, unfavourable on the whole as to the presence of hydrocarbons in it on a large scale. But, within its limits the plots, small in area, with hydrocarbon prevalence in the gas composition are distinguished. Prospects for gas presence in the region should be connected with those of them that spatially are drown to the Transcarpathian trough. One such section is the Velikobychkovk sector of the Monastyretsky sub-cover, where it is proposed to lay a parametric well 1-Velikiy Bychkov, in order to reveal the possible para-autochthon of the Vezhany sub-cover and the Paleogene of the Dilovetsky sub-cover. In addition, according to seismic data, a significant rise in the pre-flysch base is forecast in this section of the Carpathians under the Marmarosh cover. The roof of this foundation at the location of the recommended well 1-Velikiy Bychkov may be at a depth of 5000–5500 m. It may be represented by the youngest deposits of the pre-Alpine complex – the Triassic strata, industrially oil and gas saturated in the neighboring countries.

In 1957, L. G. Tkachuk and D. V. Gurzhiy have singled out the Upper Paleozoic Kuzian suite in the north-western part of the Marmarosh crystalline massif at the Rachiv area. It consists of phyllites, limestones, quartzites and dolomites. The suite is widely distributed in the Dilovets subcover of the Marmarosh nappe at the Rakhiv and Chyvchynian areas. There are two alternative points of view upon the age of the Kuzian suite. Some geologists attribute it to Paleozoic time (Upper Devonian-Lower Carboniferous), the others attribute its lower part to the Upper Paleozoic, and the upper one: to Triassic. One can notice the existence of the different estimation of the lithological composition and different estimation of the lithological composition and the volume of the Kuzian suite.Thus, in 1970 A. K. Boiko has devided it into Muntselulska (Lower) phyllite-quartzite one of Paleozoic age and Upper (Triassic) phyllite-carbonate one for which he saved the name Kuzian suite. The important is that a stratigraphic interruption was fixed between the above-mentioned units. The phyllite-carbonate Kuzian suite is dated on the basis of transgressive occurrence of the middle Triassic dolomites on it, discovery of the post-Paleozoic mosses in its lower part at the Soimul Mountain, and in the upper one: the complex of spores and pollen of Mesozoic age. Geologists, that do not recognize the idea of belonging of the part of suite to Mesozoic, indicate the next contradiction. If we accept the Mesozoic age of the Kuzian suite, so we must affirm that carbonate series of Middle Triassic-Jurassic were deposited on the massif at the same time, and 5–8 km southerly, the regional metamorphism of the Kuzian suite occurred within that zone (by the way, according to some facts at an interval of 148–178 and 175–181 mln years, and according to another information: at an interval of 196–221 mln years. This remark is not correct because the age of the Kuzian suite is Lower Triassic (251.9–247.2 mln years), but metamorphism occurred much later. In those sections where the Kuzian suite lies on the Muntselulska one, basal conglomerates consisting of pebbles and quartzitic fragments of underling suite are present in its bottom. Rocks of the Muntselulska and Kuzian suite are similar by their metamorphism intensity. For the Mesozoic Kuzian suite the manifestations of the main magmatism are characteristic, unlike the Upper Paleozoic acids. The facts testify to that the Mesozoic Kusian suite is existing, but there is a certain indefinity as to its finer dividing, stratigraphic volume and correlation with deposits of Middle Triassic. To avoid confusion, it is expedient to alter the name of the Mesozoic Kuzian suite and to name it, for example, Neo-Kuzian.

The Pohar plot is situated in the Skole district of the Lviv Region, 30 km south-west of Skole town, between Pohar and Kryve villages. Tectonically it is located in of junction of the Skybian (Slavske Skyba) and the Krosno covers. At the end of XIX beginning of XX centuries in the region of the village the oil-extracting enterprise was existent. There deposits of Oligocen and Eocene of the Rozluch belt of the Krosno cover and Oligocene of the scale of the Slavske skyba of the Skybian cover were exploited. During two ten-years of exploitation by exploring shafts and shallow boreholes more than 3 thousand ton of oil was extracted. Prospects of the Pohar plot should be connected with sand horizons of the Holovets suite of Oligocen (Klivsky sandstones) that are characterized by satisfactory reservoir properties. They are localized in the immersed part of the Hrosivsky scale of the Krosno cover separated by the Rozluch fault (tectonically screened deposit) from its forkball part, drilled in 1973–1974 1-Pohar borehole (well bottom 1935 m), due to deflection of its hole to the south-east, didn’t expose the Klivsky sandstones and didn’t solve its task. For complete exposition of the Klivsky sandstones of the Holovets suite of Oligocene of the Hrosivsky scale it is necessary to design vertically oriented 2-Pohar borehole of 2300 m in depth. About probable commercial oil-gas saturation of the horizon of the Klivsky sandstones testifies not only to the existence of the oil-extracting enterprise in the past, but the intensive surface oil shows in the stretched area that is controlled by the Rozluch fault. Moreover, taking the prospect of the zone of junction of the given covers in consideration, the seismic survey should be conducted at the Pohar area for the estimation of the geological structure of the deeper horizons and parametric borehole of 4000–5000 m in depth should be designed.