Development characteristics, models and strategies for overseas oil and gas fields

The goal of oil and gas field development is to maximize the benefits of exploitation work. In some large oilfields entering the mid-to-late development stage, to maximize the input-output ratio of oilfield exploitation, in oilfield development work, you will receive Due to the influence of many interference factors, in the field of oilfield exploitation, it is necessary to reduce the economic cost of oil and gas field exploitation as much as possible and continuously improve the economic benefits of oilfield mining units. In the mid-to-late production of oil and gas fields, the use of big data to establish a reasonable and scientific production plan for oil fields and an effective decision support system provide an important guarantee for the development and production of oil and gas fields in the middle and late stages. Through the use of effective production-increasing technology and production decision-making, comprehensively consider some oilfield mining areas and newly-added resource mining areas, comprehensively optimize and set up the development of oilfield resources in the middle and late stages and use big data technology to develop oilfields. Among them, the resource advantages are effectively transformed into economic advantages, in order to provide a good work plan for the middle and late stages of oilfield development.

Oil and gas field development geology is a branch of petroleum geology, which is gradually formed along with oil and gas field development. Oil and gas field development geology refers to the geological research work of the whole process from evaluation of exploration to the end of oil and gas field development after oil and gas field exploration and development. 2) Study the influence and interaction of reservoir characteristics on oil, gas and water performance during development;3) Provide geological data and optimize tertiary oil recovery methods. By studying the production data of Chang 2 reservoir in W oilfield, reservoir evaluation, reservoir development evaluation and reservoir development plan compilation are understood. Based on the experimental results, the evaluation results of the study area are obtained by overall analysis and evaluation of the data of the study area, which provides scientific basis for reasonable reservoir development, reserve evaluation and production performance prediction. Complete the production performance analysis of Chang 2 reservoir in W Oilfield, comprehensively process the actual geological data of the oilfield and analyze and solve the actual problems of exploration and development.

3D geological modeling technology has achieved visualization of underground reservoirs in oil and gas fields, and has been widely applied in oil and gas field development. 3D geological modeling includes structural modeling and attribute modeling, and strata and faults can be completed based on data from oil and gas field exploration and development. The porosity and permeability in the geological attribute model can be established based on logging interpretation conclusions and other relevant data, The establishment of a saturation model has always been a difficulty in 3D geological modelling. As the water saturation, is different from porosity and permeability of an oil field. Saturation is distributed under the control of factors such as gravity and capillary force, and cannot be established through spatial simulation interpolation. Instead, the influence of factors such as gravity and capillary force should be considered. This article takes the shallow sandstone M oilfield in Kazakhstan as an example, and establishes the J function of the oilfield by combining the capillary pressure experiment of the core well, in order to establish an oilfield saturation model.

Fracture, as an important factor affecting the quality of reservoirs, has always been one of the most crucial research contents in the process of oil and gas field development. The basis of research on fault systems in oil and gas field development was introduced from two aspects, namely, data foundation and research methods. The volcanic reservoir of the Yingcheng Formation in the Xudong Area of the Songliao Basin, the glutenite reservoir of the Lower Karamay Formation in a block in the northwestern margin of the Junggar Basin, and the heavy oil reservoir developed by thermal recovery in the Yulou Oil Bearing Sets in an experimental area in the western slope of the western depression of the Liaohe Basin, were taken as examples to elaborate the application of fault research in oil and gas field development from three aspects: design of volcanic gas reservoir development program, architecture analysis of glutenite reservoir, and fault systems in heavy oil reservoirs developed by thermal recovery. Based on these different Chinese examples, the difficulties and hot issues in the research of fault systems in oil and gas field development were discussed. The results show that the fine characterization of location, scale, and distribution law of faults and fractures, analysis of fault architecture of reservoirs, fine interpretation and modeling of faults, and evaluation of fault sealing property are closely related to the effective development of oil and gas fields; therefore, they should be given adequate attention in the process of oil and gas field development.

Technological progress and development directions of PetroChina overseas oil and gas field production

Background. The current state of exploration and development of oil and gas fields in the Caspian Sea is considered. Aim. Identification of new engineering and technological features of exploration and development of oil and gas fields in the Caspian Sea. Materials and methods. An analysis and typification of mining and geological conditions and parameters of oil and gas deposits, as well as traps and reservoirs, was carried out. The current state of oil and gas exploration and development in the Caspian Sea was assessed by statistical generalization and systematization of data and materials, partially borrowed from reference literature, stock sources, field data, and published works. Results. The conducted analysis revealed the main engineering and technological features of the current state of exploration and development of oil and gas fields in the Caspian Sea. These include the creation of special hydraulic structures and floating technical equipment, taking harsh marine hydrometeorological conditions for drilling prospecting, exploration and production wells into account; drilling directional clusters of wells from individual stationary platforms, pier platforms, artificially created islands, jack-up-type and semi-submersible floating installations and other structures both above and below water; selection of a rational design and number of stationary platforms, pier platforms, floating production decks, and other structures for placing the optimum number of wells; creation of special engineering means and technological processes, as well as floating installations that ensure the protection of the marine environment during drilling operations, borehole operation and repair. The need for platforms in the Caspian Sea as a whole in the period until 2025 is estimated at 71–87 units.

The Concept of the Sustainable Oil and Gas Field involves a Preventive Approach and the use of New Technologies, Innovations and Best Practices to avoid or reduce the risks of occurrence of environmental incidents and accidents achieved in a cost effective manner. This novel approach focuses on the root causes of the current gaps proposing a practical solution demonstrated on real example cases. Further it contributes to bridge the gap between non Oil and Gas Professionals evaluating the potential impact on the Environment of the core business processes related to the Exploration, Development and Field Abandonment of Oil and Gas fields. In the present Paper a method is described that supports a sustainable development and operation of Oil and Gas Fields. Further the most common reasons for the current dysfunctional procedures are analyzed as well as practical examples of the proposed approach are shown on executed projects in four continents. The proposed method builds on a preventive approach that starts with the focus of the Environmental Impact Assessment of the activities foreseen for the early project phase, as it is at this stage where the entire project can more effectively be influenced. Further the Use of fit for purpose Innovations, Technologies and Best Practices that strive to remove the risk before it happens, supports a preventive approach. The involved technologies deliver the same outcome than traditional means in a more efficient way. The mindset that the use of those Technologies comes at a higher price is challenged by the latest developments showing that those enable both an environmental friendly workflow and economical advantages to the E & P Companies. Further the above Technologies can be applied at any stage of the field life, be it at the early field development, the operational plateau or later on at the decline and abandonment phase. Several specific examples from executed Oil and Gas Projects following key elements of the presented Concept of the Sustainable Oil and Gas Field carried out in four continents are provided, showing that operating Oil and Gas fields with Zero Gas Flare, Zero Oil Spill, small footprint, no process effluents to the environment and energy efficiency can be reflected in low oil/gas unit production costs, technical and operational excellence as well as full environmental compliance. In the present paper a preventive approach to avoid and reduce environmental incidents and accidents by means of an Environmental Impact Assessment that focuses on the early project phases and the aid of fit for purpose Technical Innovations, Technologies and Best Practices is presented. This supports the goal of achieving a more Sustainable Oil and Gas Field to safely achieve production peak and increase recoverable Reserves.

A large number of oil and gas fields in the Peninsular Malaysia basin are screened (masked) by shallow gas, resulting in wipe out zones of the underlying seismic amplitudes as well as push down and time delay (sag) of the structural closure of economical oil or gas fields. Such effects lead to significant uncertainties in resolving and mapping of the objective reservoir units below the shallow gas. On these premises, 3D 4C Ocean Bottom Cable (OBC) seismic survey has been acquired and processed in one of the gas and oil fields in the Malay basin with the objective of resolving the multi-layered reservoir intervals through mode converted shear component data. This paper will discuss the rock physics and properties model that has been developed as part of a 3D 4C PP-PS Joint Seismic Inversion project with the primary objective of delineating and characterizing the various reservoir intervals and depositional environments of the oil and gas accumulation, a first in Petronas Carigali experience in reservoir characterization. This paper focuses on synthesizing missing logs, log conditioning, seismic petrophysical evaluation, rock physics modeling, invasion correction and fluid substitution to the fullwaveform (P- and S-wave) and density logs to make ready for seismic inversion. A total of 10 wells with 8 measured P- and S-wave logs are available for this study. The overall qualities of well logs were adequate for the purpose of this inversion project. These data have been used in the generation of rock physics models. The methodology applied was to construct a rock physics model that is consistent with the petrophysical analysis and the elastic properties as given by the conditioned well log data. The model was then applied everywhere to generate synthetic elastic logs and full offset synthetic seismograms that were then compared and matched to the recorded data respectively. Introduction Well log data are used to understand the relationship between the reservoir properties and subsurface seismic data. Since well log data provide constraints and calibration in the inversion workflow, their quality directly impact the confidence and the accuracy of the inversion results for quantitative interpretation and follow-on reservoir modeling. Well log quality and consistency are subjected to various factors like variation in tool measurements, borehole rugosity, borehole fluids, elapse time between drilling and logging, invasion of borehole fluids into the formations, alteration of the formation properties due to the presence of the borehole and/or borehole fluids, casing points, and missing data. Therefore, the primary goal in processing well log data is to minimize measurement related errors, generate and fill in the missing data, and to obtain consistent and accurate logs between all the wells.

3D reservoir geological modeling is an advanced reservoir description method that runs through oil and gas field exploration and development. The three-dimensional model characterizes the reservoir's geometric shape and heterogeneous reservoir property and plays an increasingly important role in determining the reservoir distribution, internal configuration, and reservoir quality. Geostatistics is an essential tool for reservoir description and modeling. A precise and accurate 3D reservoir model is significant for oil and gas exploration and development. After years of development, reservoir geological modeling technology has changed from direct conversion of geological data to two-point geostatistics driven by variogram to multipoint geostatistics. The three-dimensional geological model can indicate the spatial distribution direction and development of sand bodies; Guided by the stochastic modeling theory and variogram model theory, the 3D geological model establishes the physical property model of the reservoir under the control of the facies control model. This method can provide essential geological data for numerical simulation research, guide the distribution of remaining oil, and formulate development plans.

The use of buyback for the development of oil and gas fields is an established mechanism in Iran. Current legislation authorizes the National Iranian Oil Company (NIOC) to use buyback for both exploration and development. The buyback scheme can be defined as a risk service contract, under which the contractor is paid back by being allocated a portion of oil / gas produced as a result of providing services. Buyback is based upon a defined scope of work, a capital cost ceiling, a fixed remuneration fee and a defined cost recovery period. When buyback is used for both exploration and development, the specifications of the field to be developed are unknown at the time of contracting and therefore agreement on the scope of work, duration of development operations, ceiling for capital costs, fixed remuneration fee, and duration of cost recovery need to be deferred to the time when a commercial field is discovered. This article first outlines the introduction of buyback for development of Iran's oil and gas fields. It then examines the main features of the mechanism. Third, the use of buyback for both exploration and development is explored and related challenges discussed. Finally, the article reviews the new buyback model proposed by NIOC to address these challenges.

The development of major oil fields requires considerable primary resources consumptions. Vast use of land, water and energy, negative technogenic impact influence considerably on natural environment in local and regional aspects. Implementation of improved oil recovery (IOR) methods demands additional use of energy, expensive oil displacement agents, skilled personnel, specialised equipment etc. Multicriteria analysis of oil recovery processes by use of primary resources allows to estimate the complex efficiency and rate of natural environmental impact. To achive the solution of multipurpose problem of. rational resources consumption in course of oil fields development procedure of optimization and compromise programming is carried out. The significance of used natural resources in different geographical regions is determined by environment protection expert analysis. Natural environment systems in such regions as the North of the West Suberia and the Kaspean lowland are very sensitive to the processes of oil and gas fields development. The permafrost conditions and easy spoiled land fertile cover, the danger of earth subsidence and possible technogenic seismicity demand thorouth analysis of oil recovery projects applicability and their environmental safety. Complex efficiency assessment and multicriterion optimization of primary resources consumption have been done for the design versions of development of large oil fields Russkoe and Tengiz. Analysis of verious IOR methods on the basis of primary and energy resources consumption allows a better choice of natural environment saving technology and shows the direction and necessity of their further improvement. Study of possible technogenic effects caused by oil field development is of prime importence for timely prevention from negative consequences for nature in the region.

During the drilling of multilateral wells in oil and gas fields, the juncture in multilateral drilling is a high risk area for collapse. Studying the factors affecting the stability of the multilateral well juncture is helpful to improve the success rate of sidetracking in branch wells. In this paper, based on the experiment, the variation law of shale rock mechanical parameters before and after drilling fluid immersion is obtained. The three-dimensional model of the juncture of multilateral drilling considering the decrease of rock strength under the action of hydration is established. The angle of the main branch well and the borehole azimuth angle of the main branch well on the stability of the multilateral well juncture is analyzed. The three-dimensional Coulomb failure criterion is introduced to characterize the dynamic failure of the rock, and the failure range and failure length of the multilateral well juncture under different conditions are obtained. The results show that the smaller the angle, the more obvious the stress concentration and the longer the failure length; the smaller the azimuth, the more stable the multilateral well juncture; with the increase of drilling time, the failure range of the multilateral well juncture is gradually expanding, and after 2d, the hydration effect gradually slows down. The model can simulate the influence of different conditions on the failure range and failure length of sidetrack multilateral well juncture, and has certain guiding significance for improving the success rate of sidetrack drilling and increasing production efficiency. INTRODUCTION After continuous production in oil and gas fields, production well output decreases and some production wells may even break down leading to scrapping or shutdown, and these conditions are a common problem in the middle and late stages of oil and gas field development. If new wells- are deployed, a significant increase in economic investment is required. However, if these low-producing wells, faulty wells, and shut-in wells are transformed into an optimized new well that can be reused in the original well network, the drilling cost will be greatly reduced and old wells will be revived, dead wells will be revived, and oil fields will gain increased production (Zhu et al, 2011). Lateral drilling branch well technology is to make full use of the old well network and the re-usable well section in the upper part of the old well to drill a new borehole that can reach the target layer and be used again. Lateral drilling branch wells are widely utilized because they have the characteristics of less time, low cost, increased oil absorption area and higher recovery rate (Sun et al, 2018 and Chen et al,2022). It provides economic development and relieves energy tension.

The oil and gas complex is one of the main triggers of the industrial potential of the Russian Federation. An extremely important aspect for the Russian economy is the analysis of the introduction of intelligent digital technologies in the oil and gas industry, since it is necessary to immediately organize the transition from the traditional economy to the modern one – information, intellectual, digital. The use of digital technologies in the oil and gas industry is reduced to the automation of the entire process of oil and gas production and processing, and they are successfully integrated with digital control systems that are developed to solve the tasks of oil and gas processing enterprises in general. The article examines the features of the use of digital technologies by enterprises of the oil and gas complex at the stages of search and development of new oil and gas fields. The empirical basis of the study was made up of data on the reporting on the sustainable development of oil and gas companies of PJSC Gazprom Neft, PJSC Lukoil, PJSC NK Rosneft, PJSC Tatneft. The author identifies the problems of using digital technologies in the oil and gas industry, including: bimodal age distribution of the labor force; a significant increase in applications and data formats; global division of working groups; instant receipt of a huge amount of data in real time; a stable decrease in the number and size of new field discoveries; an increase in the cost of advanced technologies for restoring oil and gas production. In the context of the economic assessment of the search and development of new oil and gas fields, the use of an integral index of the use of digital technologies by oil and gas companies is proposed, which includes a number of indicators: the share of digital assets in the company's asset structure; the ratio of capital expenditures for digitalization of activities to the company's net profit; the share of employees with digital competencies; the share of new developed fields with the use of digital technologies; the profitability of the use of digital technologies (coefficient). The conclusion is substantiated that it is advisable for oil and gas companies to use the proposed conceptual model in order to identify the level of digitalization of the search and development of new oil and gas fields, which will allow improving the mechanism of state regulation of the country's oil and gas complex.

This article is devoted to assessing the technical effectiveness and economic feasibility of oilwell tubing in construction of intermediate supports for overhead power lines (6–10 kV) in the development of oil, gas and condensate field in the conditions of Far North. The article considers the technical possibility and economic feasibility of using the built-up cross section of the intermediate support of overhead lines consisting of two tubes welded together. The SCAD office software was used to calculate the strength of the proposed section for the design load, taking into account the impact of climatic factors. A comparative analysis of the construction cost was performed for 1 km of overhead power lines made of conventional materials and oil-well tubing. The calculations showed the feasibility of using this material for the construction of 6-10 kV overhead lines.

As the development of oilfields in China enters its middle-to-late stage, the old oilfields still occupy a dominant position in the production structure. The seepage process of reservoirs in the high Water Content Period (WCP) presents significant nonlinear and non-homogeneous evolution characteristics, and the traditional seepage-modeling methods are facing the double challenges of accuracy and adaptability when dealing with complex dynamic scenarios. In recent years, Deep Learning technology has gradually become an important tool for reservoir seepage field prediction by virtue of its powerful feature extraction and nonlinear modeling capabilities. This paper systematically reviews the development history of seepage field prediction methods and focuses on the typical models and application paths of Deep Learning in this field, including FeedForward Neural networks, Convolutional Neural Networks, temporal networks, Graphical Neural Networks, and Physical Information Neural Networks (PINNs). Key processes based on Deep Learning, such as feature engineering, network structure design, and physical constraint integration mechanisms, are further explored. Based on the summary of the existing results, this paper proposes future development directions including real-time prediction and closed-loop optimization, multi-source data fusion, physical consistency modeling and interpretability enhancement, model migration, and online updating capability. The research aims to provide theoretical support and technical reference for the intelligent development of old oilfields, the construction of digital twin reservoirs, and the prediction of seepage behavior in complex reservoirs.