Integrated analysis of fault sealing capabilities when studying and mapping hydrocarbon traps in the Dnieper-Donets Depression

• Datum: 2018
• Hauptverfasser: Okrepkyj, O. I., Tiapkina, O. M.
• Format: Artikel
• Sprache: Russisch
• Veröffentlicht: S. Subbotin Institute of Geophysics of the NAS of Ukraine 2018
• Schlagworte: Dnieper-Donets Depression; fault traps; stratigraphic traps; fault sealing capabilities; Allan diagrams; Shale Gouge Ratio
• Online Zugang: https://journals.uran.ua/geofizicheskiy/article/view/151008
• Назва журналу: Geofizicheskiy Zhurnal

This paper demonstrates how a set of advanced technologies provided a better understanding of the geological structure of the Solokha gas condensate field and underground gas storage located in onshore Ukraine. In particular, these technologies helped us improve the process of hydrocarbon trap delineation and subsequent exploration well planning in this area. The study area is structurally complex because it is located in the central part of the axial zone of the Dnieper-Donets Depression (DDD). This part of the DDD is characterized by active halokinesis that has produced morphologically developed salt bodies and associated with them plicative and disjunctive deformations of the host rocks. The structure of the area has to a large extent been formed under the impact of one of such bodies, the closely located and actively developed Bakeyski diapir. The workflow used consists in synergic integration of high-quality 3D seismic data processing, detailed structural and stratigraphic interpretation and seismic inversion combined with pore pressure measurements in wells, lithotype clustering using Kohonen self-organizing maps, and fault seal analysis. A ramified network of faults, which plays an important role in the study area, formed independent tectonic traps in the Middle Jurassic sediments of the Bayosian age and led to the compartmentalization of one of the stratigraphic traps in the Lower Carboniferous sediments of the Visean age. To analyze sealing capabilities of these faults, Allan diagrams and Shale Gouge Ratio are used. The first of these methods is based on the juxtaposition of permeable and impermeable rocks on both sides of the fault, and the second, more advanced, is based on the calculation of the percentage of the clay component of all rocks that have slipped along the fault past a given point.