scholarly journals Refinement of the petrophysical model of the Achimov formation based on facial analysis of sedimentation conditions

2021 ◽  
Vol 6 (4) ◽  
pp. 22-31
Author(s):  
Guzel R. Vahitova ◽  
Anzhela A. Kazaryan ◽  
Timur F. Khaybullin
Keyword(s):  
Oil And Gas ◽  
Facies Analysis ◽  
Pore Space ◽  
Sedimentary Cover ◽  
Clay Content ◽  
Geological Structure ◽  
Space Structure ◽  
Reservoir Properties ◽  
The Core ◽  
Promising Source

Aim. Due to the depletion of reserves of the main oil and gas complexes, the greatest interest is attributed to hard-to-recover reserves, complex-built objects of the sedimentary cover, the development of which was unprofitable until recently. One of these is the oil-bearing complex of the Achimov deposits of the Malobalykskoye field in Western Siberia. This article is devoted to the facies analysis and typification of reservoir rocks of the Achimov deposits in order to increase the reliability of determining the boundaries of the reservoirs, their interpretation and assessment of the petrophysical properties of the reservoirs. At the same time, special attention is paid to the facies analysis, which determines the characteristics of the reservoir. The Achimov deposits are a promising source of increasing resources and maintaining production at a high level. With their increasing importance, there are problems that complicate the search and assessment of deposits. Such problems include a high degree of reservoir compartmentalization, sharp facies variability, complex pore space structure, high clay content, low permeability values, etc. Materials and methods. The work is based on a comprehensive interpretation of the data of the lithological description of the core, the results of laboratory studies of the core and well logging data analysis of the Achimov deposits of the Malobalykskoye field. The methods used in the interpretation of GIS data, statistical analysis, comparison. Due to the fact that the reservoir properties of sand bodies are determined by the peculiarities of their formation in different conditions of sedimentation, it is necessary to establish a relationship between the petrophysical characteristics of rocks and their facies nature by substantiating petrofacies models. The use of the latter in geological modeling makes it possible to more effectively predict the reservoir properties (reservoir properties) of various facies lithotypes. Results. The paper presents the results of facies analysis and typification of the reservoirs of the Achimov deposits of the Malobalykskoye field, on the basis of which the boundaries of the reservoirs and the effective oilsaturated thicknesses were refined. Conclusions. Based on the results of the study, it can be concluded that it is necessary to develop refined petrophysical models for reservoirs with complex geological structure that take into account the facies features of rocks.

scholarly journals The structure of the sedimentary complex of the Middle and South Caspian depressions (Azerbaijan sector)

2021 ◽  
Vol 43 (4) ◽  
pp. 199-216
Author(s):  
N.P. Yusubov ◽  
I.S. Guliyev
Keyword(s):  
Seismic Data ◽  
Oil And Gas ◽  
Sedimentary Cover ◽  
Clay Content ◽  
Geological Structure ◽  
Point Of View ◽  
South Caspian Basin ◽  
Origin And Evolution ◽  
Geological Interpretation ◽  
High Degree

The high degree of knowledge of the upper horizons of the sedimentary cover of the Middle and South Caspian depressions, given an insufficient increase in hydrocarbon reserves, leads to the need for a detailed approach to the search for oil and gas deposits in deep-seated sediments (over 6 km). During the geological interpretation of new highly informative seismic data, as well as data of deep drilling and petrological core studies, there were revealed obvious shortcomings in the concepts of the origin and evolution of the Middle and South Caspian depressions. These ideas misinterpret evolution, especially the South Caspian Basin, which is characterized by a number of unique features: very thick sedimentary cover (up to 22 km), extremely high sedimentation rate, low heat flow and reservoir temperatures, abnormally high pore and reservoir pressures, high clay content of the section, etc. The main purpose of the study was to elucidate the regional structure and features of the dissection of the sedimentary cover of the Middle and South Caspian depressions, the conditions of occurrence and distribution of facies and thicknesses of individual complexes of deposits. The paper analyzes the results of some previous studies of the geological structure of the Middle and South Caspian depressions based on the data of deep seismic sounding, seismological and gravimetric observations. We consider the main conclusions of these studies, about the geological structure of the sedimentary complex of the region’s, very outdated and subject to revision. The results of seismic stratigraphic analysis of seismic data allowed the authors to identify new data about the tectonic structure and express a completely different point of view regarding the structure of the sedimentary cover in the region. The work also touches on the issue associated with the tectonics of the region and the alleged subduction zone here.

scholarly journals GEOLOGICAL AND GEOPHYSICAL CHARACTERISTICS OF THE ANABAR‐KHATANGA OIL AND GAS PROVINCE; NUMERICAL MODELING OF THE PROCESSES OF FORMATION OF SALT DOMES (SIBERIAN SECTOR OF THE RUSSIAN ARCTICS)

2019 ◽  
Vol 10 (2) ◽  
pp. 459-470
Author(s):  
V. A. Kontorovich ◽  
В. V. Lunev ◽  
V. V. Lapkovsky
Keyword(s):  
Cross Sections ◽  
Oil And Gas ◽  
Numerical Models ◽  
Sedimentary Cover ◽  
Ground Surface ◽  
Geological Structure ◽  
Salt Domes ◽  
Software Packages ◽  
Geological Features ◽  
Gas Bearing

The article discusses the geological structure, oil‐and‐gas‐bearing capacities and salt tectogenesis of the Anabar‐Khatanga saddle located on the Laptev Sea shore. In the study area, the platform sediments are represented by the 14‐45 km thick Neoproterozoic‐Mesozoic sedimentary complexes. The regional cross‐sections show the early and middle Devonian salt‐bearing strata and associated salt domes in the sedimentary cover, which may be indicative of potential hydrocarbon‐containing structures. Diapirs reaching the ground surface can be associated with structures capable of trapping hydrocarbons, and typical anticline structures can occur above the domes buried beneath the sediments. In our study, we used the algorithms and software packages developed by A.A. Trofimuk Institute of Petroleum Geology and Geophysics (IPGG SB RAS). Taking into account the structural geological features of the study area, we conducted numerical simulation of the formation of salt dome structures. According to the numerical models, contrasting domes that reached the ground surface began to form in the early Permian and developed most intensely in the Mesozoic, and the buried diapirs developed mainly in the late Cretaceous and Cenozoic.

scholarly journals Сomposition of volcanites from pre-Jurassic basement of the Western Siberian megabasin (Lakyuganskaya oil exploration area, YNAD)

2020 ◽  
Vol 1 (2) ◽  
pp. 7-19
Author(s):  
Vladimir Sergeevich PONOMAREV ◽  
◽  
Kirill Svyatoslavich IVANOV ◽  
Yuriy Viktorovich EROKHIN ◽  
◽  
...  
Keyword(s):  
Oil And Gas ◽  
Sedimentary Cover ◽  
Geological Structure ◽  
Island Arcs ◽  
Copper Sulfides ◽  
Geochemical Study ◽  
Dioctahedral Mica ◽  
Exploration Area ◽  
Gas Potential ◽  
First Time

Relevance of the work. The Western Siberian megabasin is the main source of oil and gas in Russia. Therefore, the study of geological structure and evolution of the development of sedimentary cover rock complexes and the basement of the region is important for estimating the oil and gas potential of this vast territory. The object of this paperis the mineralogical and petro-geochemical study of volcanites from the pre-Jurassic basement of the Lakyuganskaya area (well no. 101) of the Longyugansk exploration acreage within the territory of the Nadym megadepression of the Western Siberian megabasin. Scope of work. This work can be useful when constructing geological maps of the basement of the northern part of the Western Siberian Plate. Results and conclusions. We have studied and described the mineralogy of strongly altered volcanites from the pre-Jurassic basement of the Lakyugansk area (well no. 101) of the Western Siberian Plate. According to chemical composition, the studied volcanites are classified as moderate and high potassic basalts, andesite-basalts and andesites. The rocks were subjected to significant secondary changes in the mineral composition, such as greenschist metamorphism and propylitization. Only titanomagnetite has been preserved from primary minerals in volcanites; all other minerals were subjected to changes. In general, we have determined the following minerals – albite, clinochlore, titanite, calcite, goethite, titanomagnetite (magnetite, ulvospinel), fluorapatite, and rutile. For the first time, ferroaluminoceladonite (dioctahedral mica) and three relatively rare secondary copper sulfides – spionkopite, yarrowite, and geerite – were identified and described in basalts from the basement of Western Siberia. Sulfide coppery mineralization in the studied basalts was due to overlapped propylization processes. The rocks have features of volcanites of island arcs, as well as evidence of calc-alkali and intraplate basalts. The petrological and geochemical characteristics of the studied volcanites are similar to basalts composing the Koltogorsko-Urengoysky rift of the Western Siberian Plate.

scholarly journals Productivity Criteria for Complex Reservoirs Based on the Study of Deep-Adsorbed Gases

2021 ◽  
Vol 133 (2) ◽  
pp. 27-30
Author(s):  
D. A. Kobylinskiy ◽  
Keyword(s):  
Research Method ◽  
Oil And Gas ◽  
Geological Structure ◽  
Core Material ◽  
Test Results ◽  
The West ◽  
Gas Field ◽  
The Core ◽  
Oil And Gas Field ◽  
Complex Geological Structure

The work is devoted to the development of geochemical criteria for determining the nature of saturation for deep-adsorbed gases in the core. As the object of investigation used the core material selected in the fields in the Nadym-Pyrskoy oil and gas field. In each sample, 72 components were determined, namely, hydrocarbons of different material groups: normal, branched, polycyclic, and aromatic compounds from butane to dodecane. With respect to the quantitative distribution and correlation among the components, qualitative geochemical indicators of sediment productivity have been developed. The saturation character established by the criteria of deep-adsorbed gases was confirmed by the test results. In this regard, this research method significantly increases the effectiveness of diagnostics of prospective deposits, the application of which is relevant in the territory of the West Siberian oil and gas basin, especially when studying deep-submerged deposits of complex geological structure.

scholarly journals Mineralogical and geochemical features of volcanics from the pre-Jurassic basement of the western part of Yamal

2020 ◽  
pp. 103-114
Author(s):  
Vladimir Sergeevich PONOMAREV ◽  
◽  
Yuriy Viktorovich EROKHIN ◽  
Kirill Svyatoslavich IVANOV ◽  
Nadezhda Nikolaevna FARRAKHOVA ◽  
...  
Keyword(s):  
Oil And Gas ◽  
Sedimentary Cover ◽  
Geological Structure ◽  
Island Arc ◽  
Lead Chloride ◽  
The Arctic ◽  
Yamal Peninsula ◽  
The West ◽  
Metasomatic Process ◽  
The Yamal Peninsula

Relevance of the work. The Arctic part of the West Siberian megabasin is the main source of oil and gas in Russia, therefore, the study of the geological structure of this region is extremely important. Recently, Russia has lodged an application to extend its territory in the Arctic Ocean along the ridges that stretch from the continental shelf. Unfortunately, at the same time, we know little about the geological structure of the Arctic in the region of Western Siberia, where the thickness of the sedimentary cover is very high (about 3–4 km), therefore, the study of the basement of the Yamal Peninsula seems to be extremely urgent. The purpose of this work is mineralogical, petrological and geochemical study of dolerites from the pre-Jurassic basement of the Bovanenkovskaya area (well No. 114) within the territory of the gas condensate field of the same name, located in the western part of the Yamal Peninsula. Scope of the work. This work can be useful in constructing geological maps of the pre-Jurassic basement of the Yamal Peninsula. Results and conclusions. We have studied the mineralogical and geochemical features of dolerites from the pre-Jurassic basement of the Bovanenkovskaya area (well No. 114, sampling depth – 3210 m) of the West Siberian megabasin. The mineralogy of the rocks is represented by augite, diopside, albite, magnesian chamosite, ferrous hornblende, calcite, siderite, dolomite, anorthoclase, grossular, zeolite (gmelenite-K), pyrite, chalcopyrite, and rare lead chloride – cotunnite. The rocks underwent minor transformations in the conditions of the lower greenschist metamorphism, as well as secondary alterations in the form of superimposed propylitization. As a result of this low-temperature metasomatic process, zeolite, carbonate (calcite, dolomite, and siderite) and sulfide mineralization composed of pyrite and chalcopyrite, as well as cotunnite, which apparently replaced the dissemination of galena, were formed in the rock. Judging by geological position of the region, these dolerites are most likely formed at shallow depths during continental rifting. Remelting of the Paleozoic island arc substrate during the Early Triassic rifting and volcanism provided some closeness to the island arc trend in the geochemical features of these rift volcanics.

scholarly journals Carbonate oil and gas source rocks wettability alteration due to influence of polymer-colloidal drilling mud

2021 ◽  
pp. 17-27
Author(s):  
N. A. Skibitskaya ◽  
◽  
I. O. Burkhanova ◽  
M. N. Bolshakov ◽  
V. A. Kuzmin ◽  
...  
Keyword(s):  
Surface Properties ◽  
Oil And Gas ◽  
Pore Space ◽  
Space Structure ◽  
Source Rocks ◽  
Wettability Alteration ◽  
Drilling Mud ◽  
Rock Samples ◽  
Gas Saturation ◽  
Gas Source

Evaluation of rock wettability is an important task, since this parameter determines the distribution of water and oil in the reservoirs and their relative and phase permeability. The reliability of evaluation the wettability of rock samples depends on the drilling-in conditions during core sampling and core sample preparation methods. The investigation of the surface properties of the core from the Orenburg oil and gas condensate field showed that using of polymer-colloidal drilling mud leads to hydrophilization of the samples' surface. To obtain information on the actual wettability values of rock samples taken from wells drilled with polymer-colloidal drilling mud a method for estimating the relative (predominant) wettability of rocks based on petrophysical and lithological studies data is proposed. The authors suggest that the extraction of oil and gas source rock samples leads to irreversible changes in surface properties that cannot be restored. Keywords: selective wettability; relative wettability; predominant wettability; polymer-colloidal drilling mud; residual gas saturation; trapped gas saturation; pore space structure; extraction.

Tectonic-structural analysis of deposits in sediments of contact between sedimentary cover and basement

2020 ◽  
pp. 8-19
Author(s):  
E. S. Milei ◽  
S. R. Bembel
Keyword(s):  
Oil And Gas ◽  
Pannonian Basin ◽  
Sedimentary Cover ◽  
Geological Structure ◽  
Southeastern Part ◽  
Hydrocarbon Traps ◽  
Deep Faults ◽  
Adjacent Structures ◽  
Wide Range ◽  
Characteristic Features

The article is devoted to a comprehensive analysis of the geological structure of a complex oil reservoir located in the southeastern part of the Pannonian basin. The concept of the hydrocarbon traps formation is based on the connection with the deep processes of oil and gas formation and phenomena, which lead to the formation of cracks, faults, local positive structures in the interval from the foundation to the upper part of the sedimentary cover. The article shows the significance of deep faults in the basement during the formation of sedimentary cover structures. These processes result in a wide range of oil and gas potential of the Pannonian basin deposits. In studying the specifics of tectonic movements and the features of gravitational deposits (conglobreccia), a tectono-sedimentary approach has been developed that can reduce a number of methodological difficulties in creating geological models and concepts. Recommendations are given on the additional study of adjacent structures in order to detect hydrocarbon deposits on the slopes with protrusions of the crystalline basement. Characteristic features of the geological structure are the local volume of the identified oil and gas deposits, small foci of increased productivity and improved filtration properties of reservoirs. Such features of the uneven distribution of sites of different productivity have a significant impact on the success of prospecting and exploration, the effectiveness of development of oil and gas deposits.

scholarly journals The features of the geological structure of the Verkhnechonsky oil and gas condensate field and their influence on the field development and operation system

2020 ◽  
Vol 43 (3) ◽  
pp. 350-363
Author(s):  
L. A. Rapatskaya
Keyword(s):  
Oil And Gas ◽  
Horizontal Wells ◽  
Geological Structure ◽  
Field Structure ◽  
Gas Condensate ◽  
Reservoir Properties ◽  
Reservoir Water ◽  
Horizontal Drilling ◽  
Development System ◽  
Field Development

The study aims to analyze the relationship between the redetermination of the complexity of the geological structure of the Verkhnechonsky oil and gas condensate field and the schedule adjustment of the field development plans. The paper uses the data on the exploration and production wells obtained from the pilot operation of JSC Verkhnechonskneftegaz, the geophysical work results, and the research materials publicly available in the press. The geological structure of the Verhnechonskoye oil and gas condensate field is unique in its complexity. This is due to the following factors: a combination of tectonic disturbances accompanied by the intrusion of traps; high mineralization of the reservoir water; sharp variability of the filtration and reservoir properties of the producing horizons by area and section due to the unevenness of the lithological composition of the reservoirs, their salinization and complete pinch-out. The development system of any field should take into account the peculiarities of the field’s tectonic and lithological-facies structure, and meet specific technical and economic requirements for drilling and operating wells. The complexity of the field structure requires a thorough selection of a development system that inevitably changes as the features of the field structure are studied, e.g. vertical drilling suggested at the initial stage of the filed development was shortly after replaced with inclined-horizontal drilling with the calculation of two options. Within the pilot operation project of the Verkhnechonsky field, JSC Verkhnechonskneftegaz has developed two variants of uniform grids of directional and horizontal wells with pattern flooding for the most explored deposits of the Verkhnechonsky horizon of blocks I and II. Because of the intensive processes of the reservoirs’ secondary salinization, the flooding method required a study of the reservoir water composition. However, the proposed drilling plan using a downhole engine and gamma-ray logging could not ensure the wellbores ducting through the most productive sections of the horizon, therefore, the flow rates of some directional and horizontal wells were not high enough. To increase the drilling efficiency, the specialists of the Drilling Department (JSC Verhnechonskneftegaz), together with the Department of Geology and Field Development (Schlumberger Ltd.), proposed a new methodology that increases the drilling efficiency by using a rotary-controlled system, logging-while-drilling, and geosteering. Thus, the development system of the Verkhnechonsky oils and gas condensate field was changing in the process of specifying the field’s geological structure, anisotropy reservoir properties, and the thickness of the producing horizons in size and cut, their salinization and pinch-out, and the composition of the reservoir waters.

scholarly journals Influence of zeolitization on the migration of reservoir fluids on the example of jurassic and neocomian deposits (Yamal oil and gas region)

2021 ◽  
Vol 21 (2) ◽  
pp. 88-92
Author(s):  
Elena P. Osipova ◽  
◽  
Angela G. Astarkina ◽  
Sergey V. Astarkin ◽  
Daniil A. Strelnikov ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Gas Chromatography ◽  
Mineral Composition ◽  
Oil And Gas ◽  
Pore Space ◽  
Core Material ◽  
X Ray ◽  
The Core ◽  
Core Samples ◽  
Geochemical Studies

To assess the influence of zeolite group minerals on the migration of reservoir fluids in terrigenous deposits, complex (X-ray and gas-geochemical) studies of core material in the Yamal oil and gas region field were conducted. 54 core samples from the Pyakyakhinsky and Yuzhno-Messoyakhsky deposits were studied including 43 zeolitized and 11 non-zeolitized samples. The core samples were studied by gas chromatography to determine the content of hydrocarbons adsorbed in the pore space of the core, as well as by X-ray diffractometry to determine the mineral composition of the samples under study. The regularities of hydrocarbons distribution in the studied samples depending on the degree of their zeolization are established. The differences in the distribution of hydrocarbons in zeolitized and non-zeolitized siltstones have their own explanation. Having an ordered crystal structure and a certain size of the entrance windows zeolites are able to sorb.

scholarly journals GEOLOGICAL STRUCTURE AND OIL AND GAS POTENTIAL OF THE SOUTHERN EDGE OF THE PRE-URAL FORE DEEP

Neft i gaz ◽  
2020 ◽  
Vol 3-4 (117-1118) ◽  
pp. 69-83
Author(s):  
KH.B. ABILKHASIMOV, ◽  
Keyword(s):  
Oil And Gas ◽  
Geological Structure ◽  
Seismic Exploration ◽  
Well Log ◽  
The Core ◽  
Search Facility ◽  
Gas Potential

This article contains the lithofacies characteristic of the ShR-1 well log according to the core analyses results and the results of seismic exploration operations on Shirak site, located in the closure zone of the southern edge of Pre-Ural fore deep. The example of Shirak site demonstrates oil and gas potential of the Kazakhstan part of fore deep and describes the prospective resources. A new structure in Paleozoic sedimentary complex, which could be the first search facility in this area was discovered.

Sign in / Sign up

Export Citation Format

Share Document