Purpose. The aim of this paper is to clarify the deep structure and prospects of the oil and gas potential in the Kolomiya paleo-valley along the seismo-geotravers SG-I (67), which run along the line Nadvirna-Kolomiya-Otyniya-Ivano-Frankivsk. Seismo-geotravers SG-I (67) and partially covers the Borislav-Pokutsky cover, crosses the Sambor and Bilche-Volitsa zones, and enters the Eastern European platform. Methodology. Geological-gravitational modeling of this geological section consists in a quantitative interpretation of the anomalous of Bouguer gravity, which is based on solving direct and inverse gravity problems for complex environments and is intended to be used for the construction of optimal geological density models of the geological section. The optimal geo-density model is a model that is consistent with the observed gravitational field, does not contradict the drilling and seismic data, and takes into account the interpreter's foresight (hypotheses). The prerequisite for the reliability of this technique is its geological subordination, the use of drilling data, seismic data, and geological-tectonic maps made according to the block structure of the basement and patterns of formation of the sedimentary complex and the zones of intersection of deep faults, which are the potential routes of fluid migration, and which create favorable conditions for the emergence of structural and lithologically or tectonically screened traps of hydrocarbons. In addition, geologic-gravity modeling is used to verify, refine, and specify the structurally dense constructions, which are performed in some other way. Results. The model of the seismo-geological section along the geotravers SG-I (67) was supplemented by the densities of the strata, which were determined from the drilling and modeling data, based on the interpretational profiles located side by side. The geometry of the structures and foundation blocks, based on the results of geological and gravity modeling, was refined. The distribution of the rock densities to a depth of 20 km was also detailed. As a result of the modeling there were revealed zones of compaction and decompaction within the stratigraphic complexes. The zones of decompaction within positive forms have been identified as promising for oil exploration. Originality. Structural and density features of the geological section along the SG-I (67) geotraverse have been clarified and detailed. This made it possible to obtain new data on the deep structure of the Kolomiya paleo-valley section and oil and gas prospects in its individual sections. It is established that the common features of the covers associated with deep-fault tectonics are displayed in the anomalous gravitational field, which indicates the reliability of the forecast of the elements of the deep tectonic and structural features of the region from the data of geological-gravity modeling. Practical significance. The obtained results testify to the high informativeness of geo-density modeling in the study of the deep structure of the Earth's crust in the complex seismic geological conditions of the Precarpathian trough. The revealed reduced density zones in the Paleozoic sediments of the Kolomiya paleo-valley are promising for setting up oil exploration works.
1. Anikeyev S. G. Komp"yuterna systema rishennya pryamykh ta obernenykh zadach hravirozvidky dlya 2D/3D modeley skladno pobudovanykh seredovyshch [The computer system of solutions of the direct and inverse problems of gravity for 2D/3D models of complex environments], Rozvidka ta rozrobka naftovykh i hazovykh rodovyshch [Exploration and development of oil and gas fields], 1997, V. 34, pp. 57–63.
2. Anikeyev S. G. Metodyka interpretatsiyi hravimetrychnykh materialiv pry dovil'niy budovi heolohichnykh seredovyshch. Diss. kand. geol. nauk [Methods of the interpretation of gravimetric materials for complex geological environments. The diss. of the candidate of geol. sci.], S. Subbotin Institute of Geophysics of the National Academy of Sciences of Ukraine, Kyiv, 1999, 242 p.
3. Anikeyev S. G. Pro metodyku modelyuvannya skladno pobudovanykh seredovyshch v hravirozvidtsi [On the method of modeling complex built environments in gravity], v kn.: "Teoretychni ta prykladni aspekty heoinformatyky" [Proc. "Theoretical and practical aspects of Geoinformatics"], Kyiv, 2008, pp. 67–72.
4. Anikeyev S. G. Pro sposib shvydkoho rishennya pryamoyi zadachi hravirozvidky i mahnitorozvidky z vykorystannyam kintsevo-elementnykh aproksymatsiy [On the way to a quick solution of the direct problem of gravity and magnetic prospecting using finite-element approximations], v kn.: "Teoretychni ta prykladni aspekty heoinformatyky" [Proc. "Theoretical and practical aspects of Geoinformatics"], Kyiv, 2010, pp. 43–51.
5. Anikeyev S. G. Rishennya pryamykh zadach hravimahnitorozvidky dlya skladnykh modeley seredovyshcha za dopomohoyu shvydkoyi z•hortky [Solving of the direct problem of gravimagnetometry for complex models of environment using fast convolution]. Heodynamika [Geodynamics] (Ukraine), 2011, no. 2(11), pp. 18–20.
6. Anikeyev S., Maksymchuk V., Mel'nyk M. Heoloho-hravitatsiyne modelyuvannya po seysmoheotraversu S•H-I (67) Nadvirna-Otyniya-Ivano-Frankivs'k [Geological-gravitational modeling along the seismic geo traverse SG-1(67) Nadvirna-Otynia-Ivano-Frankivsk]. Materials of VI International scientific conference "Geophysical technologies for prediction and monitoring of geological media", Lviv, September 20-23, 2016, 309 p.
7. Bulakh E. G., Prilukov V. V. Obratnye zadachi magnitorazvedki v klasse tel, zadannykh gorizontal'nymi plastinami [Inverse problems of magnetic prospecting in the class of bodies defined by horizontal plates]. Geofizicheskiy zhurnal – Geophysical Journal (Ukraine), 1998, no. 5. T. 20, pp. 31–39.
8. Bulakh E. G. Pryamye i obratnye zadachi gravimetrii i magnitometrii. Matematicheskie metody geologicheskoy interpretatsii gravimetricheskikh i magnitometricheskikh dannykh: monografiya [Direct and inverse problems of gravimetry and magnetometry. Mathematical methods of geological interpretation of gravimetric and magnetometric data: monograph], Kyiv, Nauk. dumka, 2010, 463 p.
9. Zayats' Kh. B. Hlybynna budova nadr Zakhidnoho rehionu Ukrayiny na osnovi seysmichnykh doslidzhen' i napryamky poshukovykh robit na naftu i haz [Deep structure of the subsoil Western Ukraine from seismic surveys and prospecting areas for oil and gas], Lviv, LV UkrDGRI, 2013, 136 p.
10. Zayats' Kh. B., Anikeyev S. G. Oznaky mozhlyvoho zbahachennya korysnymy kopalynamy nadr fenomenu Kolomyys'koyi paleodolyny [Signs of a possible enrichment of minerals subsurface phenomenon of Kolomyia's paleovalley], Kompleksnoe izuchenie i osvoenie prirodnyh i tehnogennyh rossypej. Trudy IV Mezhdunarodnoj nauchno-prakticheskoj konferencii 17-22 sentjabrja 2007g. Simferopol' [Comprehensive study and development of natural and technogenic placers. Proceedings of the IV International Scientific-Practical Conference September 17-22, 2007. Simferopol], Simferopol, PolyPress, 2007, pp. 40–41.
11. Zayats' Kh. B., Korolyuk P. O., Byelovolova L. P. Poshuky novykh pastok hazu v badeni za zminamy eroziynykh form paleorel'yefu osnovy Bil'che-Volyts'koyi zony [The search for new gas traps in Baden changes erosion forms paleorelief of bases of the Bilche-Volytska zone]. Mineral'ni resursy Ukrayiny [Mineral resources of Ukraine], 2005, no 5, pp. 23–26.
12. Zayats' Kh. B., Moroshan R. P., Dovhyy I. I. Osoblyvosti davn'oho eroziynoho rel'yefu mezo-paleozoys'koyi osnovy Peredkarpat•s'koho prohynu za seysmichnymy danymy [Features ancient of erosional relief of the Meso-Paleozoic Precarpathian deep basis from seismic data]. Heolohiya i heokhimiya horyuchykh kopalyn. [Geology and Geochemistry of Combustible Minerals], 2000, no 1, pp. 60–64.
13. Kobrunov A. I. Teoreticheskie osnovy kriterial'nogo podhoda k analizu geofizicheskih dannyh (na primere zadach gravimetrii) [The theoretical basis of a criteria approach to the analysis of geophysical data (on example of the gravity problems)]. IFIOG, Ivano-Frankivsk, 1985, 269 p. Dep. Ukr. SRI STI 18.02.86 Т 1280-UK86.
14. Krasovskiy S. S., Kuprienko P. Ya., Krasovskiy A. S. and etc. Veshchestvennyy sostav glubinnykh blokov Ukrainskogo shchita, Dneprovo–Donetskoy vpadiny i Donbassa po rezul'tatam ob"emnogo modelirovaniya. Geofizika XXI stoletiya: 2002 god. Sb. trudov Chetvertykh geofizicheskikh chteniy imeni V. V. Fedynskogo (28.02. – 02.03.2002 g., Moskva) [The material composition of the deep blocks of the Ukrainian Shield, the Dneprovo-Donets Basin and the Donbass basing on the results of 3D modeling. Geophysics of the XXI century: 2002. Collected Works of the Fourth Geophysical Readings named after V. V. Fedynsky (February 28 - March 2, 2002, Moscow)], Moscow, Nauchnyy mir, 2003, pp. 76–82.
15. Mayevs`ky`j B. J., Anikeyev S. G., Monchak L. S. and etc. Novitni doslidzhennya geologichnoyi budovy` i perspekty`v naftogazonosnosti gly`bokozanureny`x gory`zontiv Ukrayins`ky`x Karpat [Recent studies of the geological structure and prospects of oil and gas horizons deeply immersed Ukrainian Carpathians]. Ivano-Frankivsk, IFNTUOG, 2012, 208 p.
16. Strakhov V. N. Reshenie obratnykh zadach gravimetrii bez resheniya pryamykh. Novye teoreticheskie, algoritmicheskie i tekhnologicheskie razrabotki v razvedochnoy geofizike [The solution of inverse problems of gravimetry without solution of direct problems. New theoretical, algorithmic and technological developments in exploration geophysics], Kyiv, Institute of Dynamics of Geospheres of the Russian Academy of Sciences, Center for Management and Marketing in the Field of Earth Sciences of the IGN of NAS of Ukraine, 2005, pp. 23–25.
17. Yegorova T. P., Kozlenko V. G., Stephenson R. A., Starostenko V. I., Legostaeva O. V. Preliminary 3-D density model for the lithosphere of the Dnieper-Donets Basin on the basis of gravity and seismic data. Geofizicheskii Zhurnal [Geophysical Journal], 1997. Vol. 19(1), pp. 124-125.
18. Yegorova T. P., Starostenko V. I. Lithosphere structure of Europe and Northern Atlantic from regional three-dimensional gravity modelling. Geophys. J. Int., 2002. Vol. 151, pp. 11–31.
19. Šefara J., Bielik M., Vozár J. and etc. 3D density modelling of Gemeric granites of the Western Carpathians. Geologica Carpathica, June 2017. Vol. 68 (3), pp. 177–192.
20. Stefaniuk M., Ostrowski C., Targosz P., Wojdyla M. Wybrane problemy magnetotellurycznych i grawime¬trycznych badan strukturalnych we wschodniej czesci Polskich Karpat [Selected problems of magnetotelluric and gravimetric structural studies in the eastern part of the Polish Carpathians]. Geologia, 2009. V. 35, no 4/1, pp. 7–46 (in Polish).