2023 - 1 - Scientific Petroleum

In order to study the heterogeneity of reservoir rocks based on core materials and well logging data, an analysis of the lithological-petrographic and reservoir properties of the rocks of the Qala suite of the PS of the Neft Dashlary field was carried out. For a more detailed study, an analysis of laboratory data on subformations (QaS1, QaS2, QaS3 and QaS4) has been carried out, the grainsize composition and reservoir properties (porosity, clay content, permeability and carbonate content) of reservoir rocks were studied. Based on the results of logging data interpretation and analysis of the constructed correlation schemes, heterogeneity, including the study of reservoirs thickness and the variability of their reservoir properties over the area have been studied.

The development and search for new prospects of oil and gas potential in the Azerbaijan sector of the Caspian Sea is one of the main tasks nowadays. The interests of research is situated in the Absheron-Balkhan tectonic zone, where such well-known oil and gas fields as Neft Dashlari, Azeri, Gunashli, Chirag, Absheron, Western Absheron, Gilovar, Darvin, etc. are located. Here the conditions of sedimentation are considered, and in the direction of drift of sedimentary material, the sources of their sedimentation are recognized. In the lower part of the geological section, considered to the sediments of the Mesozoic, Eocene, and Miocene, areas which have been identified as traps for the accumulation of hydrocarbons.

The vast majority of oil and gas fields in Azerbaijan are at the final (late) stage of development, and therefore a natural decline in production is expected. Despite the long-term development of fields, their reserves are of great industrial importance for ensuring the stability of the energy balance of our country. Therefore, it became necessary to introduce new technologies in order to maintain or partially increase production at fields that are in long-term development. Before carrying out geological activities, it is necessary to apply a new type of more modern borehole geophysical research in order to involve in the processing of zones with residual resources of these depleted fields. From this point of view, the article considers the application and results of modern borehole geophysical surveys, and analyzes the possibilities for expansion.

The drilling process is one of the most expensive steps in the construction of an oil well. Therefore, methods that reduce drilling costs without compromising the quality of well construction are always in demand by oil companies. As a rule, specialists in the field of drilling seek to increase the rate of penetration, reduce the number of round trips, eliminate accidents due to tool breaks, ensure uniform weight on bit, reduce time spent on eliminating complications, etc. Among these approaches, a special place is occupied by the technology of using vibration devices to prevent sticking of the drill string. The article presents theoretical studies of the operation of the device for dynamic impact on the bottomhole, allowing to assess the influence of design factors on its operation. The performed studies allow us to recommend the use of the device in a single bottomhole assembly to create pulsating flushing and dynamic loading of the bit. The obtained research results can be used in the design of downhole assemblies of various sizes with hydraulic vibrators for drilling wells.

The purpose of the research in the article is to develop a method for evaluating the efficiency of the water injection process. For this purpose, a number of computer studies are carried out. In view of this, a computer simulation of water injection process is applied. Using oil parameters from IX horizon of Guneshli field as PVT-properties of oil in reservoir conditions, the process of oil displacement by water injection in various technological modes is studied, the correlation between the injection rate and the amount of incremental oil production is determined. For this purpose the process of oil displacement in a hypothetical field is modeled on the basis of the idea of «enlarged well» at different injection rates, such as 10, 20, 30, 40, 50, 60, 70. and 75 m3/day. Water injection is carried out in the area of external reservoir boundary. In addition, the reservoir development process in the depletion regime is predicted for comparison. In both cases, the formation radius is considered as a circular layer equivalent to the real layer. Analysis of the obtained results determines the criteria for minimizing economic risks during water injection process. It is shown that at low rates of water injection, the numerical value of this parameter decreases with an increase of water volume injected per day. However, after a certain value of the injection rate, the efficiency factor increases with an increase of the water injected volume per day.

The oil fields of Azerbaijan are composed mainly of weakly cemented and loose rocks. Practice shows that, as a result of the destruction of natural cementing material in the process of development, testing and operation of wells, solid mechanical particles arere moved from the reservoir. During the operation of wells with weakly cemented rocks, under the action of filtration forces, as a result of the movement of fluid from the formation into the well and the stress state of the bottomhole zone of the well, the rock skeleton of the productive formation isdestroyed. The flow of fluid from the bottomholezone is accompanied by the presence of mechanical particles. Mechanical impuritie screate big problems in the operation of down hole equipment, including the operation of sucker rod pumps. Mechanical impurities prematurely disable the main parts of the pump. Larg sand particles enter the gap between the plunger and the cylinder. Grains of sand falling in to the gap between the plunger and the cylinder either jam the plunger in the cylinder or increase the gap, resulting in increased fluid leakage from the pump. To prevent sand from entering the gap, a sand-catching device has been developed. The device is being introduced into Azneft Oil and Gas Production Department. As a result of the implementation, additional oil production was obtained.