The main proven reservoirs in the shallow water sector of the North-West Black Sea Shelf and onshore Crimea are in Lower Cretaceous clastic reservoirs and in porous fractured carbonates of Upper Cretaceous to Pliocene age and in Paleocene-Eocene sandstones. Cretaceous and Tertiary shales form regional sealing horizons. Five main reservoir intervals have been identified:
- Lower Cretaceous syn-rift and post-rift clastics
- Upper Cretaceous carbonates
- Paleocene-Eocene sandstones, siltstones and carbonates
- Oligocene-Lower Miocene sandstones (Maikop Formation)
- Middle Miocene-Pliocene sandstones
The fields of the North-West Shelf are generally comprised of multilayer reservoirs within the Maikop and Lower Paleocene clastics (Golitsinskoye, Arkhangelskoye, Schmidt), Paleocene carbonates (Shtormovoye, Golitsynskoye), Eocene, Upper and Lower Paleocene (Odesskoye, Bezymyannoye), Paleocene to Lower Miocene (Maikop) sandstones (Arkhangelskoye), Upper Cretaceous Maastrichtian limestones (Schmidta), Albian sandstones (Lebada Est and Vest).
Deeper reservoirs may exist within the eroded, karstified Jurassic and Triassic carbonate sequences, on the Kalamyt High, Krayevaya Spur and in the offshore sector of the Moesian Platform, but these have not yet been adequately explored.
On the basinward flanks of major structural highs, such as the Moesian Platform, Kalamit Ridge and westwards from the Crimean Mountains, deep sea submarine fan systems shed into the deep basin during the Late Cretaceous and Tertiary drift phase can be expected. These types of geometry can be interpreted on seismic profiles of the present survey.
As the shallow waters (<100 m) of the Black Sea can be regarded as being at an immature stage of exploration, further discoveries can be expected. The deepwater (>100 m) sector of the Ukrainian Black Sea is undrilled. It is this frontier region that holds the greatest potential for substantial oil and gas finds.