Title : Geological structure and results of petrophysical studies of deposits of the pliocene stratum of the Northwestern part of the South Caspian depression
Abstract:
Relevance: In connection with the study of the oil and gas content of the deep-lying strata of the sedimentary cover of the South Caspian Basin (SCO) in Azerbaijan, geological exploration and geophysical work has been carried out to a significant extent. Scientific criteria have been prepared that can serve as the basis for future geological research. It was noted that the main deposits of oil and gas in the region are associated with the South Caspian and Kura depressions, which were intensively submerged during the Mesozoic-Cenozoic time. Despite the high prospects of the central part of the South-East Coast, its deep-lying strata, the problems associated with the extraction of oil and gas from them are not yet completely resolved.
The object of local uplifts of individual structural elements of the SCR developed mainly with the activity of the same folding mechanisms, and the overwhelming part of them are injection structures. These include local uplifts of the entire paraxial anticlinal zone of the Absheron-Pribalkhan structural mega-saddle, to which the Neft Dashlary elevation is associated. This anticlinal zone originates in the north-west from the Goshadash uplift and then through the Pirallahi-Gyurgyan-Deniz-Darwin Küpesi-Khali-Neft Dashlary-Azeri structures, etc. extends east to the rise of the Cheleken Sea. Developing in the conditions of Absheron-Pribalkhan non-classical (residual) subduction. A characteristic feature of the structures of this anticlinal zone is their formation by mechanisms of longitudinal and transverse bends with the first one dominating.
The methods :As a result, most of them are linear and elongated brachis-folds complicated by mud volcanism. Petrophysical studies were carried out on a number of areas in the Absheron archipelago. Their goal was to obtain detailed information on reservoir rocks, their lithological and petrophysical features, the refinement of hydrocarbon resources and, on the basis of the results obtained, the determination of the future directions of prospecting and exploration.For this purpose, the geological, geophysical and physical characteristics of the rocks that influenced the reservoir potential of Meso-Cenozoic sediments containing oil, gas and gas condensate accumulations in the South Kazakhstan were investigated. Such works were also carried out at the Neft Dashlary field of the North Absheron archipelago.
Thus, without having enough knowledge regarding the reservoir characteristics of the stratum, it is impossible to estimate hydrocarbon deposits and production volumes, as well as to change the direction of the survey. In addition to geological and geophysical studies conducted in this area, lithologic-petrographic and collector characteristics were studied to determine changes in conformity along the region, carbon content, porosity, permeability, density, grunlyarnogo composition and speed of sound waves of the above stratum. Accordingly, a table was compiled reflecting the reservoir characteristics of the field. The table also defined the minimum, maximum and average limits of the physical properties of rocks. The dependence of reservoir properties on the depth and their dependence on other physical factors is considered.
