«OIL AND GAS GEOLOGY» № 3/2016
HYDROCARBON RESOURCES AND RESERVES
The article considers the state of oil and gas resource base, analyzes the results of hydrocarbon quantitative estimation as of 01.01.2009 and presents main trends of it for 2009-2017. It is concluded that in new economic situation quantitative estimation of oil, gas and condensate resources should be conducted through federal targeted programs. At the same time resource potential could be estimated only involving main regional scientific centers.
OIL AND GAS POTENTIAL PROSPECTS AND EXPLORATION RESULTS
The article provides the results of zonation conducted for the folded basement of the East-Arctic shelf. It distinguisged the Grenvillian, the Baikalian, the Caledonian, the Early and The Late Kimmerian consolidation blocks, including Pre-Cambrian median masses. The map of sedimentary cover thickness that shows its distribution in area was constructed for the region. The cover is presented by two stages, they are intermediate (uneven aged) and basin (Aptian-Cenozoic). Seismic profiles in the cover section show up to 6 large seismic-stratigraphic complexes: the Upper Riphean-Vendian, the Lower-Middle Paleozoic (or Lower Paleozoic), the Upper Paleozoic-Mesozoic, the Aptian-Upper Cretaceous, the Paleogene and Miocenic-Quaternary. It was determined that the complexes formed simultaneously. The conducted stratigraphic allocation and reflecting horizons correlation could be used for age determination of seismic-stratigraphic complexes and subcomplexes in the Arctic seismic profiles sections.
The analysis of all the available information, including seismic data, shows that the Paleozoic deposits within the eastern part of the Syrdaria-basin and the south-western foothills of the Karatau ridge are composed of terrigenous-carbonate (Famenian – Lower Carboniferous) and terrigenous-evaporite (Bashkirian) deposits. These deposits are intensively dislocated and intruded by the Late Carboniferous – Early Permian granitoids. The formation history and oil-gas prospects of the Paleozoic deposits are considered.
The paper gives the assessment of the present strategy for oil and gas search in the Azerbaijan sector of the Caspian Sea. More efficient technology of search and prospecting in the deep-water part is proposed, using new scientific conceptions and modern methods and approaches.
METHODS OF OIL AND GAS DEPOSITS PROSPECTING
Afanasenkov A.P., Bondarenko M.T., Kissin Iu.M., Tarasenko E.M., Kondratiev I.K. Concerning promissing oil and gas objects for deep drilling accordning to the results of regional seismic survey in the Yenisei-Khatanga regional trough
The technique of finding and research of the lithophysical properties of the promising structures in the Jurassic-Cretaceous deposits in the territory of the Yenisei-Khatanga regional trough is shown. In case of sparse network of regional seismic profiles and remote reference well, acoustic stratum inversion of seismic data is effective. The forecast for the parameters of the traps within the limits of local structure such as reservoir thickness and reservoir and cap rocks range zones is presented.
The paper presents principle sedimentation modeling methods, they are sedimentological analysis of terrigenous and carbonate deposits, ichnofacial analysis, facies analysis according to geophysical well logging data for terrigenous and carbonate sections, lithologic-petrographic investigation of rocks in section with jointing parameters estimation. The results of sedimentation modeling are exemplified.
Integrated interpretation of geological and geophysical data provided a new insight into structure and petroleum habitat of the Polar Urals foldbelt. The study shows that the deformations observed in the Polar Urals foreland are mainly related to the thrusting and detachment faulting. The principal detachment in the sedimentary cover is provided by the Upper Ordovician evaporates pinching out in the area of the Chernyshov swell. The updated structural model permits the identification of the new large exploration opportunities. Bulk of the new gas reserves is predicted in the folded zone in front of the Urals involving large thrust-related closures. Significant oil discoveries are expected in the transition zone between the Chernyshov swell and the Kosyu Rogov foredeep which is a focus of regional hydrocarbon migration. New seismic data provide evidence for the considerable development of the hypogenic karst and dolomitization of the Serpukhovian sulphates and carbonates capable of increasing the reservoirs porosity.
Borodkin V.N., Kurchikov A.R., Variagov S.A., Nedosekin A.S., Lukashov A.V., Smirnov O.A., Shimanskii V.V. 3D CDP Seismic reflection survey for hydrocarbon resource base development of PJSC “Gazprom” companies within the Nerutinskaya depression and adjacent areas of North-Western Siberia
The paper presents hydrocarbon potential of the depression and shows that principle oil and gas prospects are connected with the mid-Jurassic and the Achimov oil and gas complexes. Also geological exploration gives evidence for the development of J1 horizon of the Vasyugan suite which is defined productive on a number of areas. According to 3D seismic survey data these sand deposits could be related to the frontal parts of the Valanginian Bazhenov suite anomalous sections. 3D seismic survey in the Jurassic-Cretaceous deposits section distinguished a range of promising complex structured objects which could not be mapped with 2D seismic survey.
Complex geochemical investigations were conducted to study microelement composition of resinous-asphaltenic and asphaltenic oil fractions. The difference in composition and ratio of certain elements was shown for oil from the deposits of different structural-tectonic zones in the region. In conjunction with bitumens geochemical differentiation data oil was divided into 3 groups related to the Varandey-Adzvin, Khoreyvey and Izhma-Pechora zones. Geophysical data for regional profiles allowed to reveal cause-and-effect relations between crustal structure, hydro-carbon accumulations location and their geochemical composition.
ECOLOGY AND PROBLEMS OF OIL AND GAS DEPOSITS DEVELOPMENT
Underground gas storages in Russia form natural-industrial systems that consist of geological environment, industrial sites and accommodation facilities interconnected with each other. The system influences all natural, geological, geodynamic, exodynamic and atmosphere processes that determine ecological situation.