Correlation of continental genesis strata: the case of the Pokur formation of the Beregovoye field

The paper analyzes one of the most important and difficult stages of constructing a geological model of the Beregovoye field when calculating hydrocarbon reserves – the correlation of the productive strata. It considers the productive strata of the Pokur formation of continental origin, analyzes the conditions of sedimentation, recommends the main correlation benchmarks and examines their characteristic features and inherent patterns.

Determining factors of the unconsolidated rocks of Cenomanian reservoir on the Bolshekhetskaya depression

The relevance of the article is associated with the importance of the object of the research. Dozens of unique and giant oil and gas fields, such as Urengoyskoye, Medvezhye, Yamburgskoye, Vyngapurovskoye, Messoyakhskoye, Nakhodkinskoye, Russkoye, have been identified within the Cenomanian complex. The main feature of Cenomanian rocks is their slow rock cementation. This leads to significant difficulties in core sampling and the following studies of it; that is the direct and most informative source of data on the composition and properties of rocks that create a geological section.The identification of the factors, which determine the slow rock cementation of reservoir rocks, allows establishing a certain order in sampling and laboratory core studies. Consequently, reliable data on the reservoir and estimation of hydrocarbon reserves both of discovered and exploited fields and newly discovered fields that are being developed on the territory of the Gydan peninsula and the Bolshekhetskaya depression will be obtained. This study is also important for the exploration and development of hydrocarbon resources of the continental shelf in the waters of the Arctic seas of Russia as one of the most promising areas.As a result of the analysis, it was found that the formation of rocks of the PK1-3 Cenomanian age of the Bolshekhetskaya depression happened under conditions of normal compaction of terrigenous sedimentary rocks that are located in the West Siberian basin. Slow rock cementation of reservoir rocks is associated with relatively low thermobaric conditions of their occurrence, as well as the low content of clay and absence of carbonate cements. Their lithological and petrophysical characteristics are close to the analogous Cenomanian deposits of the northern fields of Western Siberia and can be applied to other unconsolidated rocks studied areas.

An Integrated Approach to Well Logging: The Case of the Bazhenov Formation

New geological structures – displaced blocks of salt diapirs’ overburden – were identified in the axial part of the Dnieper-Donets basin (DDB) beside one of the largest salt domes due to modern high-precision gravity and magnetic surveys and their joint 3D inversion with seismic and well log data. Superposition of gravity lineaments and wells penetrating Middle and Lower Carboniferous below Permian and Upper Carboniferous sediments in proximity to salt allowed to propose halokinetic model salt overburden displacement, assuming Upper Carboniferous reactivation. Analogy with rafts and carapaces of the Gulf of Mexico is considered in terms of magnitude of salt-induced deformations. Density of Carboniferous rocks within the displaced flaps evidence a high probability of hydrocarbon saturation. Possible traps include uplifted parts of the overturned flaps, abutting Upper Carboniferous reservoirs, and underlying Carboniferous sequence. Play elements are analyzed using analogues from the Dnieper-Donets basin and the Gulf of Mexico. Hydrocarbon reserves of the overturned flaps within the study area are estimated to exceed Q50 (Р50) = 150 million cubic meters of oil equivalent.

Carapaces of the Dnieper-Donets Basin as a New Exploration Target

New geological structures - displaced blocks of salt diapirs’ overburden - were identified in the axial part of the Dnieper-Donets basin (DDB) beside one of the largest salt domes due to modern high-precision gravity and magnetic surveys and their joint 3D inversion with seismic and well log data. Superposition of gravity lineaments and wells penetrating Middle and Lower Carboniferous below Permian and Upper Carboniferous sediments in proximity to salt allowed to propose halokinetic model salt overburden displacement, assuming Upper Carboniferous reactivation. Analogy with rafts and carapaces of the Gulf of Mexico is considered in terms of magnitude of salt- induced deformations. Density of Carboniferous rocks within the displaced flaps evidence a high probability of hydrocarbon saturation. Possible traps include uplifted parts of the overturned flaps, abutting Upper Carboniferous reservoirs, and underlying Carboniferous sequence. Play elements are analyzed using analogues from the Dnieper-Donets basin and the Gulf of Mexico. Hydrocarbon reserves of the overturned flaps within the study area are estimated to exceed Q50 (P50) = 150 million cubic meters of oil equivalent.

The UNFC Concept and the Possibility of its Application in Azerbaijan

Moving towards sustainable development, Azerbaijan joining SDG Agenda 2030 adheres to the policy of developing both hydrocarbon and non-hydrocarbon resources for economic diversification. At the same time, efficient resource management becomes a vital process at the governmental and transnational companies’ levels. Therefore, a competent classification and structuring of all reserves and resources will be inevitable soon to improve their accurate estimates and effective management in various aspects, including resource availability, technical feasibility, and environmental-socio-economic viability. The importance of the latter is indisputable since social and environmental stability is an essential component of the country's sustainable economic development policy. From this perspective, the United Nations Framework Classification for Resources (UNFC) is seen as a tool to help accomplish these tasks and provide simple screening and verification procedures for evaluating future investment projects. Given that hydrocarbon reserves make a significant contribution to the economy, a study on the application and adaptation of UNFC to local petroleum resource management has been granted as a pilot project to assess the feasibility of its further implementation for other energy and mineral reserves and resources of the country. The UNFC current state analysis as a global standard for classifying energy and mineral resources and their applications is carried out to launch the project. The review covers various case studies, including the classification of hydrocarbon reserves and resources (HCRR) using UNFC (Mexico project, transition projects to the classification of the Russian Federation, etc.), as well as mineral resources in different countries. The research primary goal is to screen different approaches and techniques to assess the practicality of their application to petroleum reserves and resources of Azerbaijan in transferring currently used old Former Soviet Union HCRR classification to UNFC, possibly via PRMS. In addition, a Case Study Research based on the Field A data in Azerbaijan is conducted.

Combined Usage of Different Geosteering Methods and Vendor Independent Bed Boundary Mapping in Complex Geological Environment on a Real-Life Example from West Kazakhstan

Summary Drilling lateral wells nowadays is considered to be the most widely used method for producing hard-to-recover hydrocarbon reserves. Technologies used while geosteering the well are developing rapidly making high-level geosteering the key for cutting costs on drilling and enhancing well production. Due to low prices for hydrocarbons, oil companies are trying to find new, up-to-date approaches that will allow them to reduce capital and operating expenses while still enhancing the efficiency of drilling wells in target zones. One of such technology will be shown in this abstract through the example of a successfully drilled well in Akingen oilfield, Republic of Kazakhstan.

Oil Saturation Index in Hydrophobic Carbonate Reservoir: Evaluation Aspects

Hydrocarbon reserves in carbonate reservoirs account for 38% - 60% of total world reserves, according to different estimates. In Tatarstan, carbonate reservoirs are found, mostly, in the eastern slope of the Melekess Depression and the South-Tatarian Arch. The carbonate reservoirs are confined to the Middle and Lower Carboniferous sediments, the Upper Devonian (including the domanik sediments), and the Upper Permian (the Kazanian heavy oil accumulations). Considering an extensive geographic and stratigraphic range and differing tectonic and sedimentation environments, the carbonate rocks are characterized by a variety of reservoir properties. In contrast to terrigenous rocks, the carbonate void space is complicated by secondary processes that took place much later than the sedimentogenesis-lithogenesis stage. Numerous fissures, caves, sutures, and stylolites form the void space of the reservoir rock matrix containing commercial hydrocarbon reserves. In addition to fracturing and vugginess contributing to increase of void space of carbonate rocks, the secondary processes include sulphatisation and secondary dolomitization (in limestones), adding to deterioration of reservoir properties. The secondary processes impede understanding and evaluation of reservoir properties and saturation potential, in particular, determination of the oil and gas saturation factors (Dyakonova T.F. et al, 2019, Akhmetov R.T. et al, 2017)/ In the western slope of the South-Tatarian Arch, carbonate reservoirs are confined to the Middle and Lower Carboniferous sediments. Numerous RCAL and SCAL investigations provided valuable insight into these targets. In this paper, we used data from the laboratory experiments and studies of core and oil samples from the six neighbor fields on the western slope of the South-Tatarian Arch. Because of common sedimentological and tectonic sedimentation environments and lithological similarity of rocks within the stratigraphic referencing, the six fields under analysis were considered as analogous, and the results of the laboratory studies of the samples were reviewed collectively.

An integrated approach to evaluate the hydrocarbon potential of Jurassic Samana Suk Formation in Middle Indus Basin, Pakistan.

The Indus Basin is considered as prolific hydrocarbon-bearing province of Pakistan. The study area is located in the Middle Indus Basin. Two wells (Bagh-X-01 and Budhuana-01) were drilled in the vicinity of the study area to determine the hydrocarbon potential of the area. Both wells show no hydrocarbon reserves and are thus abandoned. The present study emphasizes two-dimensional subsurface seismic interpretation and rock physics evaluation to estimate reservoir properties of the Jurassic Samana Suk Formation. Data from nine 2-D seismic lines and two wells have been utilized to evaluate the potential. The time contour maps indicate the existence of subsurface structural features in the study area. With the help of the 3-D geological model, the faults are marked in the Samana Suk Formation and the structure is identified as a monocline. The 3-D geological modeling results also reveal that Samana Suk Formation tends to become thin in the northeast, and thick in the southwest. The petrophysical interpretation was performed to find the hydrocarbon potential of the Formation. The cross plot between P-impedance and Vp/Vs ratio shows that the lithology cannot be differentiated by the logs. Rock physics parameters such as Poisson’s ratio, bulk modulus, shear modulus, shear wave velocity, primary wave velocity, Vp/Vs ratio, and density indicate that there are no considerable hydrocarbon reserves in the Samana Suk Formation.