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Date submitted2024-04-16
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Date accepted2024-09-24
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Date published2024-11-12
Deep-buried Lower Paleozoic oil and gas systems in eastern Siberian Platform: geological and geophysical characteristics, estimation of hydrocarbon resources
The study of deep-buried oil and gas systems is a promising trend in the preparation of hydrocarbon resources. The study of the factors determining oil and gas potential is extremely important. The Lena-Vilyui sedimentary basin in the eastern Siberian Platform has a potential for the discovery of large oil and gas fields in deep-buried Cambrian deposits. The use of original methodological approaches to the analysis of black shale and overlying deposits, generalization of the results of lithological, biostratigraphic and geochemical studies of Cambrian deposits in territories adjoining the study area, modern interpretation of geophysical data showed that siliceous, carbonate, mixed rocks (kerogen-mixtite) of the Kuonamka complex and clastic clinoform-built Mayan deposits are most interesting in terms of oil and gas potential. Oil and gas producing rocks of the Lower and Middle Cambrian Kuonamka complex subsided to the depths of 14 km. The interpretation of modern seismic surveying data confirms the hypothesis of a limited occurrence of the Upper Devonian Vilyui rift system. Based on generalization of geological, geophysical and geochemical archival and new materials on the Lower Paleozoic deposits of the eastern Siberian Platform, a probabilistic estimation of geological hydrocarbon resources of the Cambrian and younger Paleozoic complexes in the Lena-Vilyui sedimentary basin was performed. Based on basin modelling results it was concluded that the resources were mainly represented by gas. It is presumed that oil resources can be discovered in traps of the barrier reef system as well as on the Anabar and Aldan slopes of the Vilyui Hemisyneclise. With a confidence probability of 0.9, it can be stated that total initial resources of oil and gas (within the boundaries of the Vilyui Hemisyneclise) exceed 5 billion t of conventional hydrocarbons. The recommended extremely cautious estimate of resources of the pre-Permian complexes is 2.2 billion t of conventional hydrocarbons. In the study area, it is necessary to implement a program of deep and super-deep parametric drilling without which it is impossible to determine the oil and gas potential of the Lower Paleozoic.
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Date submitted2020-12-08
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Date accepted2021-10-18
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Date published2021-12-16
Prospects for the oil and gas content of the Upper Permian deposits of the southwestern part of the Vilyui syneclise based on the analysis of sedimentary environments and geochemical conditions of oil and gas content
The article discusses the prospects for the oil and gas content of the Upper Permian deposits in the southwestern marginal part of the Vilyui syneclise. In this margin, the Permian terrigenous complex with proven oil and gas productivity in the central part of the syneclise, pinches out. The study area, represented by the monoclinal slopes of the Vilyui syneclise, is considered a promising area for the exploration of non-structural hydrocarbon traps in the Upper Paleozoic sediments. The objectives of the study include identifying general patterns of sediment formation, associated mainly with the development of the alluvial complex, and substantiating the potential opportunities of migration and accumulation of hydrocarbons in the predicted traps. The research is based on the interpretation of the latest seismic surveys and prior-years geological and geophysical data. Authors carried out structural and paleo-structural analysis, identified lithofacies in the well log, generalized and analyzed the geochemical conditions of the oil and gas content of the Upper Permian deposits, traced the pinching out of the Upper Permian deposits on the southwestern margin of the syneclise, and also outlined areas of river valleys development that form zones of advanced reservoirs. The results of the studies have validated promising oil and gas accumulation zones on the southwestern slopes of the syneclise associated with non-anticlinal hydrocarbon traps. Authors also drew up a diagram of the oil and gas potential of the Upper Permian deposits. The obtained results are of interest for prospecting for oil and gas in the area under study.
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Date submitted2009-08-19
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Date accepted2009-10-02
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Date published2010-02-01
The estimation features of vulnerability and desintegration оf subway construction materials in Saint Petersburg
- Authors:
- P. V. Kotyukov
In this paper the features of subway construction materials degradation depending on engineering-geological, hydro-geological and geoecological conditions of Saint Petersburg underground space are considered. The basic types of subway construction placing and their destruction specificity depending on influence of water-bearing horizons hydrodynamic and hydro chemical conditions, natural and natural-technogenic gas bio-production and microbial activity are analyzed. The examples of the disintegrated materials and new growths (salt efflorescence, stalactites and others) chemical compound features depending on the content of ground waters basic components affecting on tunnels lining are resulted.
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Date submitted2008-10-12
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Date accepted2008-12-17
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Date published2009-12-11
Principles of development of geological engineering and geological criteria for safe burial of low radioactive wastes in lower cambrian blue clays in the Leningrad region
- Authors:
- R. E. Dashko
It is noticed that the chosen territory for nuclear-waste disposal in Lower Cambrian clay massif nearby Koporje of Leningrad region takes place in a tectonic zone. Lower Cambrian clays are considered as the block-fractured rock mass having a depth zone structure. The long radioactive irradiation of dark blue clays has led to transformation of their structure, physical-chemical and physical-mechanical properties, and also to activization of microbial activity. Nine criteria to the geoenvironmental and engineering geological characteristics allowing in a complex to estimate safety and reliability of a nuclear-waste disposal in clay formations on an example of dark blue clays are suggested.