On the basis of lithologic-facial, mineralogical-petrographic, sedimentological-paleooceanographic investigations for the first time for the Black Sea-Crimean region the lithologic-facial and lithmologic models of deposits of Middle and Upper Maikop were constructed, their mineralogical and petrographic features were studied, sedimentological-paleooceanographic reconstructions for separate age intervals were made, the lithophysical structure of the Middle Maikop layers, in which the gas prospective objects are localized, was determined.
Sedimentological-paleooceanographic models allowed establishing the features of spatial-temporal variations of facial conditions for the Late Oligocene and Early Miocene, and creation of models of the lithophysical structure of the Middle Maikop deposits at separate sections. As a result, the features of spatial-temporal development of different type reservoir-rocks (porous, fractured) and reservoirs of different rank are determined. In general, there is a tendency of the porous type reservoirs domination at the northern and southern sides of the Black Sea megadeep, and substitution by the fractured type reservoirs of the in its axial zone. The sedimentary environments at the beginning of Late Oligocene (strata Ms-I) retained the main features that were inherent at the beginning of the Early Oligocene time.
In the Black Sea (southern) part of the shelf basin the shallow-water depositional environments prevailed. The terrigenous sedimentation of the shelf plains dominated here, where, under the influence of the flows of the northwest direction the bodies of long shore bars were formed. At the end of the Late Oligocene (strata Ms-III) sedimentary conditions within the region have undergone some changes. The intensity of terrigenous dumping from the Moldovian land has decreased. The main volume of clastic material in the sedimentary basin came from the north-east. The situation of the Late Maikop sedimentation within the limits of the Skif shelf, in comparison with the Middle Maikop, differed by the decrease in the basin area and its depth.
The discharge of clastic material was provided by river systems (Pre-Dnister and Pre-Dnipro), which is fixed by elongated areas of development of sands, which at dipping the shelf are replaced by sediments of mouth bars, barrier islands and fans.
A number of gas prospecting objects of different types were distinguished in the Middle Maikop. Prospective objects in traps of anticline type. At Golitsyna area there are two horizons of combined (fracture and pore reservoirs) in the lower and middle parts of the section. At the area of Schmidta there are promising porous reservoirs in the middle part and combined in the lower part of the section. At Mizhvodenskaya area the development of three reservoirs that are made up of fracture reservoirs is projected. Four level objects (from top to bottom) are located at Shtormova area: the first and the second are represented by the reservoirs of the fracture, the third - the pore, the fourth - the combined (pore and fracture) types. At the area of Arkhangelska there are three thick strata of reservoirs. From the upper one the commercial gas flow has been produced. Instead, the two lower ones lack sufficient structural preconditions for the formation of an anticlinal trap, so these targets are considered as conditionally perspective. Perspective objects in traps of lithological type. In the Tendrivsko-Tavriyskij area at the upper part of the section of the Middle Maikop is predicted a long stretching pinching out band of the mainly pore reservoirs, while in Odesko-Osetrovij – the fracture ones. Within the Karkinitsko-Borisovskoyi area in the middle part of the section the horizon of fracture reservoir-rocks is wedging out, and in its lower parts such features are observed in two strata of porous reservoir-rocks.
