Productive Horizons Research Articles

ANALYSIS OF THE EFFECTIVENESS OF STIMULATION METHODS AT THE TRIZ FACILITY — PREOBRAZHENSK PETROLEUM PRODUCT HORIZON, EASTERN SIBERIA

The history of prospecting and exploration of oil and gas fields within the Nepsko-Botuoba Anteklisa (NBA) and the eponymous oil and gas region (OGR) of the Leno-Tunguska Oil and Gas Province of the Siberian Platform dates back more than half a century. The base object of exploration for a long time remained the terrigenous deposits of the Venda reservoir. A number of large, medium and small hydrocarbon deposits are associated with them. The beginning of a systematic study of the northern regions of the Irkutsk region was the receipt of oil inflow from the Markov reference well in 1962. In 1971, the Yaraktinskoye gas condensate field was discovered north of Markovsky. In 1970, a parametric well was drilled within the Preobrazhensky uplift, which made it possible to identify a productive carbonate horizon (Zone B12), from which a gas inflow was obtained after hydrochloric acid treatment. Further continuation of the complex of geophysical studies east and south of Preobrazhenskaya Square made it possible to identify a number of positive structural forms. In the Chonsky zone, several local complications were identified — Chonsky, Molchalunsky and Verkhnechonsky structural noses, recommended for setting up area studies of MOU. The Preobrazhensky horizon (Zone B12) ranks second among the pay zones in terms of potential in-place reserves. It is the extremely low filtrationcapacitive properties of the natural reservoir and the harsh thermobaric conditions at the pressure of oil saturation with gas close to the initial reservoir pressure that is the basis for classifying these reserves as hard to recover (RHR).This article discusses the methodological features of drilling and completion of oil producing wells with a horizontal end of a long length, ascending inclined boreholes, multi-hole horizontal wells (MHW), conducting MHW, large-volume MKO and KGRP in the carbonate natural reservoir of the Preobrazhensky productive horizon (B12) of one of the fields of the Nepsky arch in the north of the Irkutsk region. The oil reserves of this tank are classified as difficult to recover (RHR). Research and search for new approaches to the development of the TRiZ facilities of the Preobrazhensky carbonate horizon in this field is today the most important task. The main results of the testing of the complex of geological and technological measures (GTM) are summarized, including a new effective technology for conducting multi-stage hydraulic fracturing, which is planned for use in the further full-scale development of the oil reservoir.

The nature of the gas content of the Nejelinsky formation

The paper deals with the issue of regional gas content of Nejelinsky formation of the Lower Triassic. Based on the consideration of the peculiarities of the gas content of Nejelinsky formation and the upper productive horizons of the Permian age within the Khapchagai megawall; it is concluded that there are two types of deposits in the section of Nejelinsky formation. The first type of deposits is gas-hydrodynamically limited in the volume of Nejelinsky formation and is genetically related to breakthrough gases from the Permian part of the section. The second type of deposits is gas-hydrodynamically related to deposits in the upper part of the Permian productive horizon. Due to the lack of its own gas formation potential in Nejelinsky formation outside the Khapchagai and Loglorsky shafts; it can only be considered as an effective fluid barrier. It is concluded that in the absence of isolated deposits in Nejelinsky formation; favorable reservoir properties in the Permian part of the section should be expected.

THE PROBLEM OF PRESERVING THE RESERVOIR PROPERTIES OF PRODUCTIVE HORIZONS – THE CURRENT STATE

The reasons for the deterioration of reservoir properties of productive layers during their opening are considered. Special attention is paid to the study of geological properties of emulsions of the drilling mud filtrate – oil type. Productive deposits on the example of the fields of Southwestern Turkmenistan are characterized by a complex and ambiguous composition of rocks, waters and drilling mud and oil. Each of the components, interacting with the filtrate of the drilling mud, determines the deterioration of reservoir properties and a decrease in the flow rates of hydrocarbon fluids. Oilbased solutions were used to open productive horizons while maintaining natural permeability, as well as for drilling in particularly unstable clay saline deposits. In such solutions, the dispersion medium is represented by diesel fuel, and the dispersed phase is finely ground oxidized bitumen. The results obtained make it possible to clarify the mechanism of reducing the reservoir properties of productive formations due to the penetration of filtrate of drilling fluids, as well as to formulate new requirements for technologies, composition and properties of drilling fluids for opening productive formations.

Structure and formation conditions of the Yarakta productive horizon of the Late Vendian in the southern part of the Nepsko-Botuobinskaya Anticlise

The relevance. Eastern Siberia is a region with large raw material resources that plays a crucial role in development of Russian oil and gas complex. Since the 1970s, active exploration for hydrocarbons has been underway in the Nepsko-Botuobinskaya Anteclise. One of the main targets for development are terrigenous Vendian deposits, in which up to half of the region hydrocarbon reserves are concentrated. Therefore, for optimal development of the fields confined to them, a detailed study of lithological factors of formation of terrigenous reservoirs is required. The main aim. Lithological and facies analysis is used to reconstruct and trace the evolution of sedimentation conditions of the Yarakta productive horizon of the Nepa Formation. Objects. Terrigenous deposits of the Yarakta productive horizon of the Upper Nepa subformation of the Upper Vendian Formation, uncovered by deep drilling in the area of the Yarakta field. Methods. Mineralogical-petrographic study of core material, facial analysis of lithological rock types, correlation. Results. The Yarakta productive horizon was formed during Late Nepa time. At that time, there was a partly subaerial and to a greater extent subaerial delta plain (lower delta plain) within the tidal plain. It is assumed to be a delta of advancement on a coast dominated by tidal activity and to a lesser extent by wave activity (mixed type of coast). In the subsequent transgression, in the late Nepean time (upper part of the strata), a bar system began to form in place of the delta plain with the bars advancing toward the coastline in the northwestern direction. The bars had an elongated lentil-shaped shape along the conditional coastline. During the formation of the bars, due to the active wave and tidal activity, the sediments carried out by the delta were redeposited and re-sorted. At the Late Nepa and Early Tertiary boundary, the entire area was a shallow intertidal and terrigenous sebha (lagoon) with clay-siltstone sediments and sulfate-carbonate inclusions in them; sometimes, sandy sediments of small intertidal channels or sandbanks are noted in them. Improved filtration-capacitative properties are associated with the facies of distributary subaquatic channels and large (active) tidal channels.

Сomparative analysis of oils from carbonate sediments of Upper Usolskaya subformation and ediacarian-cambrian productive horizons in central part of Nepsko-Botuobinskaya anteclise

The focus in study of the central part of Nepsko-Botuobinskaya anteclise is concentrated on the subsalt oil and gas bearing horizons of group B (Osinsky, Upper Ust-Kutsky, Lower Ust-Kutsky, Preobrazhensky horizons) and V (terrigenous formations of Vendian age). However, higher, in the Lower-Middle Cambrian carbonate-halogen deposits, there are also promising horizons of group A (Kelorsky, Atovsky, Khristoforovsky, Balykhtinsky), oil and gas presence of a sufficient amount of the Angara-Lena stage, the northern part of the Nepsko-Botuobinskaya anteclise and adjacent structures. The paper examines the results of geochemical studies of oil samples from the Osinsky horizon (layer B1) and the nameless dolomite layer located between the salts in the lower part of the Upper Usolskaya subformation, previously considered gas-bearing at best. The conducted studies by the method of chromatography-mass spectrometry and comparison of the geochemical parameters of oils from different reservoirs show the similarity of hydrocarbon fluids of the Upper Usolskaya subformation and lower productive horizons, which makes it possible to attribute them to a single oil and gas bearing system.

USE OF REAL OPTIONS TO EVALUATE THE PROFITABILITY OF BIOGAS PRODUCTION FROM STILLAGE IN THE TEQUILA INDUSTRY

In Mexico, the tequila industry is the second most important economic activity within the alcoholic beverage industry, after the beer industry. Tequila vinasse is wastewater with a high organic load produced during the distillation of the fermented must of the blue agave (Agave tequilana Weber var. azul), which has a great impact on soils and water bodies in the tequila region. On the other hand, the decrease in fuel reserves causes instability in hydrocarbon prices, which makes it necessary to implement alternative fuel methods such as biogas. In this sense, it has recently been pointed out that the anaerobic digestion process is the most suitable for the treatment of tequila vinasse since it allows the removal of contaminating organic matter, together with the production of biogas that can be used in situ in the tequila industry. In this study, the financial feasibility of the production of biogas for self-consumption from tequila vinasse was calculated with the values achieved from a pilot system composed of a packed bed reactor (PBR) with technological and economic advantages to treat this waste. Profitability was evaluated over a 10-year production horizon (net present value $1 569 001) and was complemented with the Real Options methodology, taking into account price volatility and the option to expand. The results showed that the project is profitable with the 42.85 % biogas production expansion option. It is concluded that biogas production is financially feasible and it is possible to increase the profitability of the system by $6 325 109 if production is expanded.

DIRECT COMPARISON OF MEASUREMENTS OF GEOPHYSICAL FIELDS WITH LITHOLOGICAL HETEROGENEITY OF THE JURASSIC PERIOD AT THE FIELD OF BUZASHY VAULT

Often, production geophysics is the main and widespread method in the oil and gas industry. Well logging curves have the most complete characteristics when they are based on the study of direct material, which is the core. This scientific project is mainly aimed at studying the relationship of reservoirs of different generations and their facies belonging, which contribute to a more correct understanding of the structure of exploitation objects, taking into account lithological heterogeneity and dissection of productive horizons. Application of the practical value of knowledge of the features and patterns of formation of sand bodies in the further development of the field, in order to increase oil recovery factors. In this article, we compare reservoir intervals composed of both medium and coarse-grained sandstones with well logging data, and consider their spatial distribution according to seismic-attribute analysis based on 3D seismic data. Further, based on the results of the spectrometric gamma logging on the core, the core and well logging were linked in order to more accurately determine the petrophysical properties of lithofacies. In conclusion, brief conclusions of practical and laboratory work are summarized and final conclusions are drawn.

Combined Method of Intensification of Borehole Uranium Mining in Ores with Low Filtration Characteristics

The purpose of this study is to develop an effective method for increasing the filtration characteristics of ores during borehole uranium mining, depending on the geological characteristics of ores and host rocks. At the same time, it is planned to increase the productivity of production and the pick-up rate of injection wells, increase the period of uninterrupted operation of equipment and reduce operating costs for production. The geotechnological parameters of borehole uranium mining on technological blocks of various mining and geological conditions are investigated and evaluated. Core material samples were taken and the structures and compositions of the host rocks of the Santonian, Maastrichtian and Campanian ore intervals were determined by microscopic method. Based on a comparative analysis of the methods used to intensify borehole production, a combined method for restoring the permeability of the productive horizon was developed. The effective parameters of the combined well regeneration method combining fluctuations of compressed air pulses with chemical reagents – solvents are calculated and justified. The possibility of reducing the processing time of wells by a new method and increasing the productivity of wells is discussed. The method of calculation and application of the combined method of intensification of borehole production of uranium in ores with low filtration characteristics has been developed.

Analysis of structural-tectonic and petrophysical features of productive horizons of Mishovdag fold


 
 
 The article analyzes the geological structure, lithofascial, tectonic, and morpho- logical features of the Mishovdag oil field, which is a productive area in terms of oil content. Morphologically, it represents a brachianticlinal fold located in the north-west and south-east directions. The Mishovdag fold is located on the Kalamaddin-Bandovan anticline zone between the Kichik Harami (in the northeast) and Galmaz (in the northwest) structures. The Mishovdag-Galmaz part of the anticlinal zone extends in the sub-southern direction. The structures included in the zone are represented on the surface mainly by Aghjagil, Absheron, and ancient Khazar sediments. Productive layer sediments come to the surface in few areas. The tectonic movements and activity of mud volcanoes (active or buried) have left characteristic traces in the geological structure of the research area. Brachianticlinal and other types of structures were formed here. Under the strong influence of tectonic movements, the layers forming them were deformed and broken into blocks by regional tectonic faults. The anticlinal structures of the zone are complicated by longitudinal and latitudinal faults. The Mishovdag fold is represented by a brachianticline, 20-25 km long and 4-6 km wide. Brachianticline has a sharply asymmet- rical structure. The southwestern limb is steep, and inclined at an angle of 25-450, while the northeastern limb is flat and characterized by an inclination angle of 7-250. As a result of the analysis of the cross-sections of deep wells drilled in the field, it was determined that Mesozoic, Paleogene-Miocene, and Pliocene-Anthropogenic sediments are developed in the section of the fold. Sediments repre- senting the cross-section are characterized by high reservoir properties. Geological-geophysical works are carried out in the field. Core materials were taken from wells. The lithological-petrophysical characteristics – carbonate, porosity, and permeability of reservoir rocks have been determined according to core samples taken from exploration wells drilled in the field. The lithological-petrophysical characteristic regularities of change were investigated depending on depth.
 
 

GEOCHEMISTRY FEATURES OF ALUMINUM IN OILS AND CLASSIFICATION OF THE DEPOSITS OF THE DNIPRO-DONETSK DEPTH ACCORDING TO ITS CONTENT

Problem Statement and Purpose. The purpose of this publication is to establish, on the basis of geochemical studies of oils, the specifics of the relationship between aluminum concentrations and the content of other impurity metals, the values of the main mining, industrial and technological parameters and indicators of oils and their deposits, and to develop a natural classification of oil deposits on the example of Dnipro-Donetsk depth by content aluminum. Solving the task of the article will contribute to the development of a set of predictive criteria for hydrocarbon accumulations and the scientific substantiation of the geological-economic, technological and ecological assessment of their use, which in turn determines the relevance and practical value of the conducted research. Data & Methods. The factual basis of the work was the results of analyzes of metal content in oils from 36 deposits. At least 30 oil samples from each deposit were tested for metal content using X‑ray fluorescence analysis on an energy-dispersive spectrometer. All values of metals concentrations and their technological parameters were normalized to bring the information to the same scale, regardless of the units of measurement and the scale of the samples. Calculated normalized values of indicators of oil samples from each deposits were processed using the STATISTICA 11.6 program, which performed the calculation of descriptive statistics, correlation, regression, cluster analyzes and graphical visualization of the results of the performed studies. Results. It has been proven that the aluminum content in the oils of the considered deposits is inversely correlated with the following factors: concentrations of Ni, Fe, asphaltenes, the average capacity of the productive horizon, the current temperature of the productive horizons, the values of the current pressure in the productive horizons, the current depth of the productive horizons, the mineralization of the reservoir water from productive horizons, the density of formation water from productive horizons. And direct correlation with paraffin content, oil viscosity values, resin content, boiling point, V / Ni concentration ratio, total metal content, oil density values, Zn, Mn, S, Hg, Cr, V, Co concentrations. A natural classification of Dnipro-Donetsk depth deposits based on aluminum content in oils has been developed. The results of correlation and cluster analyzes were interpreted in genetic terms, which made it possible to establish a list of deposits formed by oil of abiogenic origin.

Features of the structure, study and development of a unique geological object of the Republic of Komi – the Nizhnechutinskoye oil field

The modern idea of the geological structure of oil deposits of the Nizhnechutinskoye field is presented. The uniqueness of the field lies in the shallow depths of productive deposits. The oil-saturated layer is 100 m. The shallow depths of productive formations led to low formation temperature and pressure. Under such conditions, oil is inactive, characterized by high viscosity, and dissolved gas is practically absent. The features of the formation of the sedimentary cover in the area of the field predetermined the block structure, while the rocks of the productive horizon are characterized by a complex system of vertical fractures, which greatly complicates the process of oil recovery. A distinctive feature of the studied section of the field is the presence of effusive rocks underlying the main productive stratum and overlapping the lower productive layer. The article systematizes the results of field trial operation, which revealed a number of complicating factors, which is associated primarily with the uniqueness of the geological structure of the studied deposits. Despite the solid history of studying the Nizhnechutinskoye field, which has almost 300 years, given the negligible depth of productive deposits, oil production at this field still remains a difficult task.

A renewable energy optimisation approach with production planning for a real industrial process: An application of genetic algorithms

This article presents the formulation of the optimisation of a manufacturing process, through genetic algorithms, managing the generation and demand of energy in a factory at periodic moments of time. The strategy manages to minimise the daily energy cost and maximise the use of installed renewable energy, also taking advantage of potential battery banks. A time series with a 24-hour horizon of energy production from renewable sources and the electricity supply prices provided by the electricity market operator has been considered. Furthermore, in the simulations, scenarios with different battery capacities have been tested, which has allowed a preliminary study to be carried out for the installation of the electrical storage bank. The results presented in this work show that 6% of energy costs can be saved per day, compared to the current management decided by the manufacturing plant operators.

FOAM ACID FRACTURE AS AN ALTERNATIVE TO STANDARD FRACKING AND LIQUID-LESS METHODS OF ROCKS LIQUIDATION

The article discusses the issue of the resource potential of tight terrigenous gas-saturated reservoirs, which lie at significant depths within the central part of the Dnipro-Donetsk oil and gas-bearing region, and ways to solve problems related to the methods of development of these deposits, since they are non-convective and cannot be extracted by the classical method. Within the scope of this issue, the article considers the method of hydraulic fracturing as one of the most effective ways of causing the inflow of hydrocarbons from the productive horizon and intensifying the development of hard-to-extract deposits. An overview of fracturing substances used for the process of densification of rocks, in particular, liquids based on water, hydrocarbon, acid bases, liquid-free methods and foam systems, was performed. The compositions of the reagents, the features of their use, and their main disadvantages are listed. Examples of world experience in the use of well-known fracturing fluids and fluid-free methods of reservoir densification are given.In this work, attention is focused on increasing the permeability of rocks through the use of foam acid systems, since, as experience shows, they are highly effective in conditions of tightand heterogeneous reservoirs due to their selectivity, they can be adapted to rocks of various lithological and mineralogical composition and a wide range thermo-baric conditions, they have satisfactory transport properties and the ability to cause self-cleaning of the well.The main reasons for popularizing the use of methods of loosening rocks with a minimum liquid content in the composition of explosive substances for unconventional gas deposits of Ukraine are highlighted. It is recommended to carry out work on the creation of more effective, ecological and economically profitable new or improvement of existing disintegrants, especially foam systems.

New Data on the Age of Ozernoe Polymetallic Deposit (Western Transbaikal)

The article presents the results of biostratigraphic and U-Pb geochronological (detrital zircons) studies of the volcanic-terrigenous lacustrine member of the upper subformation of the Lower Paleozoic Oldyndinskaya Formation, which contains pyrite-polymetallic ores of the Ozernoye deposit (Kurbino-Eravninsky ore region, Western Transbaikalia). The first, second and “crystal tuff” productive horizons of the first ore-bearing level of the ozernaya member were studied. It is represented by an alternation of tuffs, calcareous, siliceous, carbonaceous tuffites, pelitomorphic limestones, limestone gravelstones with interlayers and lenses of mine-ralized tuff-conglobreccia and layers of banded siderite pyrite ores. For the first time, bryozoans, algae, and palynoflora were found in calcareous tuffaceous siltstones and limestones of the second and “crystalline tuff” productive horizons. These data indicate the Early Carboniferous, Tournaisian time of sediment accumulation. The results of U-Pb geochronological studies of detrital zircons from the mineralized tuff-conglobreccia of the third productive horizon limit the lower limit of the rock formation time as not older than the Late Cambrian.

Multi-Product Production Optimization of Maintenance Integrated into the Control Chart Under Service Level and Quality Constraints

This work proposes a combined production, maintenance, and quality control for a supply chain management system. In this work, we consider a joint model production system consisting of a single machine producing multi-products connected to a multi-warehouse to satisfy changing and characterized customer demand for all the products throughout the production horizon. The work will answer some managerial questions about which product to produce and how much each is to make. Then the need for a maintenance strategy corresponding to the optimal production plan. The unreliable production system is prone to random failure, directly impacting product quality. The variance in production rate, inventory management, and utilization affects the status of the production system and its maintenance evolution. The control of the process and its quality is carried out using a multi-level statistical process control (SPC) and its tool, “control chart of average.” The goal is to create a constraint optimization model that reduces total cost while meeting changing customer requests across many warehouses and over time. We consider the impact of production rate on the production machine degradation, the increasing failure model, and maintenance methods based on the optimal parameters of the control chart.

The effect of clay minerals on in-situ leaching of uranium

In recent years, with the development of techniques and methods for in-situ leaching (ISL), additional uranium extraction from previously worked-out blocks is becoming not only relevant, but also quite achievable. In this case, the extraction of residual uranium reserves from previously worked-out blocks does not require additional costs for the necessary infrastructure. One of the most important factors in the formation of residual uranium reserves in worked-out blocks is the presence of clay minerals in the ore horizon. In this regard, we conducted a number of studies on the adverse and positive effects of clay minerals on ISL process. Water permeability and relatively good filtration (not less than 0.5–1 m/day) of ores and rocks of a productive horizon (aquifer) is the most important hydrogeological factors affecting the performance of uranium ISL. The second most important hydrogeological factor is the lack of fluid communication between the productive aquifer and nonproductive aquifers, i.e., the obligatory presence of aquicludes. The role of clays in these hydrogeological factors is twofold. On the one hand, the presence of clays negatively affects both the solutions filtration rate and uranium extraction. On the other hand, the presence of clay minerals (forming an aquiclude) enhances the effect of ISL. The study findings allowed the role of clay minerals in uranium ISL to be assessed. The diffusion coefficients of nitrate ions in the clays were determined, and the protective effect of aquicludes was calculated. The effect of the clay content in the ore sand horizon on the solutions filtration coefficients was also established. The static uranium exchange capacity of clays was determined by studying the process of uranium sorption by clay samples from sulfate and bicarbonate solutions. The studies established the diffusion coefficients of nitrate ions in montmorillonite and kaolinite clays, which amounted to 3.34 10−6 and 2.14 · 10−6 cm2/s. Taking into account the calculated values of diffusion coefficients, the protective time of the clayey aquiclude for nitrate ions was 43 years. At 20 % clay minerals content, the solution filtration coefficient decreases to values where ISL conditions become unfavorable. It was found experimentally that the sorption of uranium by clay minerals depends on both the nature of the clays and the composition of the solution. Uranium sorption from sulfate solutions proceeds noticeably better than that from bicarbonate solutions. The highest values of the static uranium exchange capacity were obtained for bentonite (104 mg/g).

Conditions for formation of technogenic reservoirs (on the example of the Rudkivske gas field)


 
 
 The practical experience of long-term operation of hydrocarbon deposits con- firms the presence of geomechanical processes and their significant impact on the state of the gas-saturated massif of rocks. In fields that are being operated for a long time, the prospects for industrial hydrocarbon accumulation can be associated with secondary gas traps of non-traditional type, in particular, technogenic ones, which are formed in low-pore collectors. The authors carried out a detailed analysis of the well-known gas and gas condensate fields of Ukraine. The Rudkivske gas field of the Western oil-and-gas bearing region was chosen. The purpose of the study is to clarify the geological conditions for the formation of technogenic collectors and attracting additional volumes of gas under the action of a geomechanical factor while operating the Rudkivske gas field. The quoted results of the research prove the effect of gas extraction from the deposits of the J-h horizon on the formation of secondary technogenic collectors by attracting additional volumes of gas from the of ND-4, ND-5, ND-7 productive horizons and the formation of a new (ND-10) one, which subsequently connected to the gas production. Attracting additional gas volumes is due to the gas influx from newly made technogenic collectors, which were formed under the action of a geomechanical factor in the process of long-term development of the field. The formation of technogenic collectors occurred due to the compression of the main reservoir of the Jurassic age (J-h), the deformation of the rock strata, and the decomposition of the overlying rocks, the development of the crack propagation, permeability increase and gas recovery rising. The geomechanical factor management opens the prospect of obtaining additional industrial gas influx in the late stages of the development of gas and gas-condensate fields, by predicting the geological conditions for the formation of improved secondary filtration and capacitive properties favorable to form technogenic gas deposits.
 
 

Assessment of the deep oil and gas bearing potential onshore in the west of Azerbaijan (Tarsdallar area)


 
 
 The Tarsdeller oil and gas field, which has a brachyoanthicline structure, is the most promising area of the oil-gas region (OGR) in the Kura-Gabirri interfluve. Goal: Based on the reservoir characteristics of rock samples obtained from exploration wells drilled in the area adjacent to the field, petrophysical models have been compiled, reflecting the spatial variation in porosity and permeability of oil-containing reservoirs. Objects: Consideration of the petrophysical properties of core samples taken in the study area made it possible to confirm the oil and gas potential of deep-seated reservoirs. Methods: This analyzed the values and variation of petrophysical properties by depth, age and various physical factors. The observed wide range of changes in the reservoir properties of rocks in the study area is mainly due to tectonic changes, lithological heterogeneity of the sedimentary complex, differences in the depth of bedrocks, as well as the complexity of tectonic conditions. As a result, to predict the oil and gas content in deep reservoirs of the same structures, it is advisable to use the methods of exploration geophysics, as well as the results of changes inthe reservoir characteristics of rocks, determined by petrophysical data. At the same time, it is most expedient to focus on the study of Paleogene-Cretaceous tectonics for the search for oil and gas objects using prospecting and exploration (preferably aerial-photo-space) works at the field. Results: Models made in 3D format illustrate the predicted oil and gas potential and patterns of distribution of productive horizons involved in the geological structure of oil and gas deposits, along the depths and stratigraphic units. It is shown that although the permeability of the rocks in the area is low, the porosity values are favorable for the industrial accumulation of hydro-carbons. Fractured carbonate reservoirs of the Upper Cretaceous are the most promising among the Mesozoic sediments in the OGRbetween the Kura and Gabirri rivers. Deep-seated structural uplifts complicated by large-amplitude fractures are recommended as the priority targets for further geological exploration. However, the real potential of the Eocene deposits, which are widespread in the NGR between the Kura and Gabirri rivers, remains unexplored by deep drilling. This is due, on the one hand, to the incomplete opening of the Eocene section in the structures prepared for deep drilling, structural-tectonic and lithofacies features, as well as insufficient knowledge of drilling for oil and gas, and on the other hand, poor development of promising intervals of the section.
 
 

Seismogeological model of the terrigenous vendian deposits on the north–eastern slope of the Nepa-Botuoba anteclise

A seismogeological model of the junction zone of the Nepa-Botuoba anteclise and the Ygyattinskaya depression was built based on the results of a comprehensive interpretation of deep drilling and seismic data. The position and propagation of regional high-rank faults have been specified, and a model of tectonic faults of the study area has been constructed. All faults of the study area were divided into three classes: those that cut the entire sedimentary cover; developed in the lower part of the sedimentary section, fading in the Cambrian salt pack; complicating the upper post-salt complex of rocks. Criteria for identifying thinning zones were developed and were made use of to identify oil and gas perspective objects within the Talakh, Ulakhan and Kharystan productive horizons.

Peculiarities of the total content of metals in oil deposits of the Dnipro-Donetsk depression

Purpose. To establish the peculiarities of the total content of metals in oil deposits of the Dnipro-Donetsk depression and to develop a classification of deposits by this indicator. Methodology. The factual basis of the research was the results of analyzes of metals in oil from 36 deposits of the Dnipro-Donetsk depression. With the help of X-ray fluorescent analysis, at least 30 oil samples from each deposit for metals content were investigated. The deposits are selected according to the principles of maximum completeness of geochemical information, their finding in different oil and gas areas of the Dnipro-Donetsk depression, different composition of the oil system, different geological types of traps, different structure of deposits and different ages of oil collectors. X-ray fluorescent analysis was performed on the energy-dispersive spectrometer "SPRUT" SEF 01. The time of accumulation of the spectrum 600 sec. Preparation and analysis were carried out according to the standard of ASTM D 4927 - "Determination of the elemental composition of components of lubricants by X-ray fluorescent spectroscopy with dispersion by wavelength". Correlation and regression analysis was carried out by methods that were implemented in the most popular professional statistical software platforms "Statistica" and "SPSS" and their analysis in geological concepts. Findigs. To evaluate the central characteristics of the total content of metals in oil, the deposits considered more correctly use not the arithmetic mean, but the median. It is proved that the total content of metals in oil considered is associated with a reverse correlation connection with resin content, the values of the modern temperature of the productive horizon, the modern depth of productive horizon, the mineralization productive horizons; and direct correlation with the concentrations of nickel, manganese, mercury, chromium, vanadium, aluminum, cobalt, zinc, iron, paraffin, asphalt, sulfur and oil viscos boiling and oil density. Scientific novelty. It consists in the development of the natural classification of oil deposits by the overall content of metals, and to establish a connection of this indicator with the concentration of individual elements of impurities, the main components of oil and the main geological and technological indicators of deposits of the Dnipro-Donetsk depression. Practical significance. Is to establish the concentrations and the possibility of forecasting the total content of metals in the Dnipro-Donetsk depression, which in turn provides the opportunity to solve the topical problems of practical direction. The solution of a number of industrial-raw materials based on the assessment of oil as an ore raw material, since the content of some elements in them sometimes exceeds ore concentrations, so there is a possibility of their concomitant industrial removal from by-products during processing processes. The solution of technological issues, which are caused by the negative impact of some elements contained in oil, on the geological environment, production technologies and the equipment used in the course of their extraction and processing.