Abstract:The shale oil in the continental faulted basins in eastern China，represented by Jiyang shale oil，has made a breakthrough in production capacity. However，Jiyang shale oil faces great challenges in achieving high and stable production due to the large burial depth and thickness，low maturity，high formation temperature and pressure，and poor oil flow capacity. Based on the production practice of more than 90 horizontal wells and 10 000-meter cores，the ternary-element storage and flow theory of“ storage，fracture，and pressure” was deepened，and the key technology system of Jiyang shale oil development，such as three-dimensional fine evaluation of sweet spots of shale oil development，policy optimization for three-dimensional development technology，and threedimensional balanced fracturing technology，was formed under the guidance of the theory. Theoretical research and practice show that pores and multi-scale and multi-type micro-fractures constitute a double reservoir system，which is the material basis for high and stable production and controls the reservoir space and the law of oil and gas accumulation. The support fractures and the hydraulic fractures are coupled to form a double fracture system with a scale of nanometer to centimeter. It has the characteristics of a cascade start-up and is the flow path of high and stable production. Energy increase by fracturing can effectively improve the flow capacity of pores and increase the imbibition displacement efficiency under the premise of good formation pressure retention. At the same time，fine pressure control can realize collaborative coupling of energy fields，which can further release the production capacity of shale oil reservoirs. The double pressure coordination of pressure retention and pressurization is the energy guarantee for high and stable production. The key development technology system guided by the theory of ternary-element storage and flow provides effective technical support for the production capacity breakthrough of multi-sag multilayer systems，which is of great significance for promoting the large-scale beneficial development of shale oil in continental faulted basins in eastern China.

Abstract:Chemical flooding is one of the essential means to enhance oil recovery and has played an important role in the efficient development of oilfields. Based on the current development status of chemical flooding technology in China and abroad，the theory and technology of chemical flooding for enhanced oil recovery in Shengli Oilfield were systematically summarized in response to the harsh conditions of high temperature and high salinity reservoirs. This article reviewed the theoretical and technical challenges overcome in the development of chemical flooding technology from indoor research to field application and introduced the development process of chemical flooding in high-temperature and high-salinity reservoirs of Shengli Oilfield over the past 60 years. By understanding the interaction and structure-activity relationships between oil displacement agents and between oil displacement agents and crude oil，Shengli Oilfield iteratively created the theory of“ equal emphasis on viscoelasticity and expansion” for polymers in high-temperature and high-salinity reservoirs，the theory of“ similar enrichment of oil agents and anionic non-ionic additive efficiency enhancement” for surfactants，and the theory of“ control flooding by deformation” for viscoelastic particles. Shengli Oilfield also developed polymer flooding technology，alkali-free binary composite flooding technology，and heterogeneous composite flooding technology for high-temperature and high-salinity reservoirs with the characteristics of Shengli Oilfield and overcame the problem of significantly enhancing oil recovery in reservoirs with a temperature of 85 °C and a mineralization of 30 000 mg/L. The annual oil production of 96 chemical flooding projects implemented in the field has accounted for over 11% of the oilfield’s production for 20 consecutive years. This series of technologies has made important contributions to the stable production and sustainable development of the Shengli Oilfield.

Abstract:This paper systematically investigated the progress of laboratory research and field application of biochemical composite enhanced oil recovery technology in the past 10 years in China and abroad. The synergistic mechanism between oil recovery bacteria，biosurfactants， biopolysaccharides， and chemical oil recovery agents such as surfactants， polymers， and nanoparticles was discussed in terms of improving displacement efficiency and expanding swept volume， respectively. In addition，the system construction and field application effects were analyzed. The results show that the combination of biological bacteria and their metabolites with chemical oil recovery agents has synergistic effects on interfacial tension reduction， emulsification dispersion， mobility ratio control，and viscosity reduction of heavy oil，and the field application has achieved good application results. Bacteria polymer composite profile control and microbial desulfurization and viscosity preservation technologies were explored in Shengli Oilfield， and estimated recoveries reached 9% and 10.3%，respectively. Biological ASP composite technology was applied in Daqing Oilfield，and the recovery of the pilot area has been improved to 22%. The biochemical composite enhanced oil recovery technology has great potential for application in the exploitation of difficult-to-recovery reserves in mature oilfields. The next step is to continue to deepen the synergistic mechanism between biological and chemical systems，innovate the integration and implementation process of biological and chemical oil recovery systems according to the differences between reservoir planes and inter- and intra-layers，refine the implementation plan for different development stages and reservoir spaces， and maximize the advantages of biological and chemical synergistic efficiency enhancement technologies through the three-dimensional balanced development of reservoirs to satisfy the demand for sustainable development of mature oilfields.

Abstract:Jiyang shale oil resources have enormous potential. However，there is a lack of systematic understanding of seepage mechanism and development laws in the multi-scale spaces after fracturing due to the influence of complex geological conditions，making it difficult to achieve large-scale beneficial development. In order to clarify the formation mechanism of the development law of Jiyang shale oil，the multi-scale fracture characteristics of Jiyang shale oil were analyzed. The formation mechanism and combination mode of fracture networks after fracturing were studied using physical experiments and numerical simulations. In addition，seepage mechanisms in multi-medium spaces were researched， including the stress sensitivity of multi-scale fractures，nonlinear flow in multi-scale pores and fractures， and imbibition displacement of pore-fracture systems. According to the differences in the distribution of multi-scale fracture networks and their flow laws after fracturing，a three-zone flow pattern of“ easy flow-slow flowdifficult flow” for shale oil was established. Finally， the flow characteristics and production laws of Jiyang shale oil at different flow stages were clarified. The research results indicated that the developed bedding fractures could improve the physical properties of reservoirs， enhance imbibition displacement efficiency， and reduce start-up pressure gradient. During the elastic development stage， the flow channels reduce， and the fracture network conductivity decreases as the formation pressure declines，resulting in significant stress sensitivity. In the development process of Jiyang shale oil， the initial flow state is mainly dominated by linear flow and elliptical flow of fractures supplied by the easy flow zone. In the middle stage of development， the slow flow zone supplies energy to the easy flow zone， and the flow state changes to elliptical flow in the formation. Moreover， the shale oil in the difficult flow zone is gradually produced， and the flow state changes to boundary-controlled flow in the later stage of development. Due to the influence of geological conditions and production systems， there are significant differences in the energy change， water cut decrease，and production change law of different horizontal wells. Reasonably optimizing the shut-in time and production system can ensure imbibition displacement efficiency， efficiently utilize formation energy， and improve shale oil production capacity.

Abstract:Shengli Oilfield has abundant low-permeability oil reservoirs with proven reserves of 1.18 billion tons， presenting a good prospect for development. However，there is a problem of inability to inject and produce during the development process of the oil reservoirs due to the low porosity， poor permeability，and strong heterogeneity of the low-permeability oil reservoir. A systematic review was conducted on the prediction and analysis methods for low-permeability oil reservoirs in Shengli Oilfield to achieve efficient development of low-permeability oil reservoirs， as well as efficient development technologies，and the advantages and disadvantages of existing technologies were analyzed to provide an outlook for the development technologies of low-permeability oil reservoirs.Based on research and practice， the following conclusions are drawn：① Shengli Oilfield has developed fine reservoir characterization technologies such as reservoir prediction， in-situ stress prediction， and evaluation of reservoir heterogeneity. ② Based on theoretical and technological innovation，the physical limit of reserve production was constantly broken，forming differential development technology series，such as water injection development technology of horizontal wells in ultra-low permeability oil reservoirs，long well section multi-stage fracturing development technology of horizontal wells in tight oil reservoirs，well pattern adaptation technology for enhanced oil recovery of general low-permeability oil reservoirs，pressure flooding technology in lowpermeability tight oil reservoirs，and viscous emulsion-surfactant flooding technology. Good development results have been achieved. ③ Combined with the actual needs of high-quality development and speed and efficiency improvement development of low-permeability oil reservoirs in Shengli Oilfield， the well pattern reconstruction technology of dual control streamline variation，CCUS technology，and nanobubble flooding technology were proposed， pointing out the development direction for improving oil recovery of low-permeability oil reservoirs.

Abstract:The influence of fractures on the mechanical properties of shale rocks is prominent. Accurately characterizing the changes in the mechanical properties of fractured shale is an essential basis for precisely depicting the four-dimensional in-situ stress field during the fracturing and production process of shale reservoirs. Existing studies on four-dimensional in-situ stress often attribute stress changes primarily to alterations in pore pressures， neglecting the impact of changes in the mechanical properties of rocks on four-dimensional in-situ stress. The relationship between the pore pressure and the volume of shale pores and fractures was clarified by utilizing online CT experiments. Theoretical relationships among fracture volume， Poisson’s ratio， and elastic modulus of shale rocks were derived based on strain energy theory. Furthermore， a time-varying theoretical model was established with pore pressure， Poisson’s ratio， and elastic modulus as variables. The results indicate that the opening of bedding fractures is the primary cause of the time-varying nature of the mechanical parameters of shale rocks. The number of fractures opening increases， and the fracture space exhibits exponential growth as pore pressure increases. With the increase in fracture volume， the Poisson’s ratio of shale rocks rapidly increases， while the Young’s modulus rapidly decreases， leading to a significant reduction in shale strength. An analysis of the shale in Jiyang Depression reveals that Young’s modulus decreases from 37.5 GPa to 15.06 GPa， and the Poisson’s ratio increases from 0.22 to 0.35 when the proportion of fracture volume increases to 1%. The influence of the time-varying nature of mechanical parameters of rocks on the evolution of four-dimensional in-situ stress is comparatively analyzed through numerical simulation methods. The four-dimensional in-situ stress simulation， considering the time-varying characteristics of rock mechanics，can better characterize the law of stress evolution and direction deflection during shale fracturing and production. It is more consistent with the evolution law of four-dimensional in-situ stress in the process of fracturing and production， and the simulation results are more reliable. The research results can provide theoretical support for the rational deployment， optimal design， and risk warning of three-dimensional well groups of shale oil.

Abstract:Shengli beach-shallow sea oilfields are located at the junction of sea and land， with Chengdao Oilfield and Xinbei Oilfield as representatives. They have the characteristics of diverse reservoir types， complex ground conditions， and significant investments in ocean engineering facilities， so it is difficult to develop beneficially. Based on the development practice of the Shengli beach-shallow sea oilfield， this paper focused on the technical achievements since the“ 11th Five-Year Plan.” The efficient development technologies for characteristic Shengli beach-shallow sea oilfields were formed through continuous technical research， with the cores of subdivision and comprehensive adjustment of beach-shallow sea oilfields， overall injection and production regulation of beach-shallow sea oilfields， efficient development of offshore oil production， effective utilization of beach-shallow sea marginal oilfield，and development of complex fractured buried hill oil reservoir. The first beach-shallow sea oilfield of four million tons，Chengdao Oilfield， was built in China， realizing the crossing from land to sea. The challenges in the efficient production construction in the new area and the technical support of enhanced oil recovery in the mature area were clarified by analyzing the problems facing the high-quality development of the beach-shallow sea oilfield. By considering the important position for the continuous production of Shengli Oilfield， the development direction of“ fewer wells， high yield， high speed， and high efficiency” was proposed to alleviate the contradiction between the production demand and low grade of unproduced reserves， as well as the stable production foundation and restrictive liquid production in the mature area faced by the beach-shallow sea oilfield in the future. In other words，it is necessary to continue to study critical technologies， such as the beneficial utilization of multiple oil and gas reservoirs in beachshallow sea， the reconstruction of secondary well pattern under the“ 3 + 2” development mode based on platform intensification， and the intelligent injection and production control based on a big model， to support the high-quality and sustainable development of Shengli beach-shallow sea oilfield.

Abstract:In order to realize the effective development of shale oil with low maturity in continental faulted basins in Jiyang Depression，systematic evaluations have been carried out simultaneously in Boxing， Niuzhuang， and Minfeng sags since 2019， based on the 10 000 meters of systematic coring and more than 100 000 core tests. Significant breakthroughs have been made in single well evaluation and stereoscopic development of well groups. A pilot test of eight wells in three layers was conducted in Boxing Sag， and the first 100 000-ton shale oil development well group of SINOPEC was built. A large-platform stereoscopic development test of well groups was carried out with 20 wells in five layers， and all wells were put into production in Niuzhuang Sag. A comprehensive overall evaluation and stereoscopic development test was launched in Minfeng Sag， following the mode of“ overall deployment of a large platform and step-by-step implementation of a small well group.” Peak daily oil production exceeded one hundred tons in 28 wells， including Wells FYP1 and FY1-1HF ternary-element （storage， fracture， and pressure） storage and flow theory of shale oil in Jiyang Depression was proposed. The technologies of shale oil development， stereoscopic fine evaluation of development sweet spots， integrated modeling and numerical simulation， and stereoscopic development optimization were developed. A theoretical and technical system of stereoscopic development of shale oil in continental faulted basins with Shengli characteristics was initially constructed. It effectively supported the construction of the shale oil national demonstration area in Jiyang Depression， Shengli Oilfield.

Abstract:Water-flooding reservoirs are the mainstay in developing mature oilfields in eastern China，and they have entered the ultra-high water cut stage as a whole after long-term water injection development. Laboratory studies and field practice show that there is still potential for significantly enhancing oil recovery. However，the difficulty of scientific and efficient development has increased due to the heterogeneity of reservoirs and development dynamics， and further research is needed to enhance oil recovery technology. Uncompartmentalized reservoirs face challenges such as severe extreme water consumption in the later stage of ultrahigh water cut，affecting stable production and enhanced oil recovery through water flooding. Therefore，the theory of high water consumption zones was deepened， and the development technology of near-resistance layer recombination，the vector development technology of ultra-high water cut reservoirs， and the development technology of flow field adjustment in the later stage of ultrahigh water cut were developed through innovation，achieving water consumption control and reduction，with an average oil recovery of 43.7%. In response to the characteristics of fault block reservoirs with numerous faults and small fault blocks，as well as the challenges of small remaining oil reserves and difficult exploitation during the ultra-high water-cut stage， understanding of the accumulation patterns of remaining oil and hydrodynamic regulation mechanisms was deepened. A series of leading development technologies were developed through innovation， such as artificial peripheral water flooding and stereoscopic development， improving reserve control and water flooding efficiency， with an average oil recovery of 29.4%. These technologies have supported the stable and profitable production of fault block reservoirs. Given the poor physical properties of low-permeability reservoirs and the difficulty of effective water flooding， nonlinear flow mechanisms and pressure flooding development mechanisms were researched， supporting development technologies were formed， and the development limits were constantly broadened. A series of differential development technologies have been innovated， such as water injection of simulated horizontal wells in ultra-low permeability reservoirs，well pattern adaptation for enhanced oil recovery in general low-permeability reservoirs， and pressure flooding in lowpermeability and tight reservoirs， with an average oil recovery of 15.7%， realizing rapid and efficient development of lowpermeability reservoirs. Through the above technical research， the efficient development of water-flooding reservoirs in ultra-high water cut stage is realized. According to the development characteristics and situation of different types of reservoirs， the directions for further enhancing oil recovery of water-flooding reservoirs are being put forward.

Abstract:In view of the geological characteristics and development contradictions of different types of heavy oil reservoirs in Shengli Oilfield， a set of development technologies for heavy oil reservoirs have been developed， and remarkable development achievements have been obtained. In this paper， the progress of development technologies for different types of heavy oil reservoirs was summarized in the theoretical basis and the field application. For heavy oil reservoirs after many rounds of huffing and puffing，the well pattern infilling technology was formed based on the non-Darcy flow theory. For sensitive heavy oil reservoirs， the adverse impact of water sensitivity on development was reduced based on the proposed theory of near heat and remote prevention. For extraheavy oil reservoirs， HDCS technology was applied through the synergistic viscosity reduction and energy enhancement due to the expansion to solve the development problem of difficult injection and production. For inefficient water-flooding heavy oil reservoirs，the flow lines of infilled corner wells and water wells were changed by turning to steam flooding to enhance oil recovery. For deep heavy oil reservoirs， the multi-thermal composite oil displacement theory was formed， and deep heavy oil reservoirs were effectively produced based on the understanding of the synergistic interaction mechanism of gas-heat synergy for heat retention and enhancing steam chamber， heat-agent synergy for replacing viscosity reduction and improving flooding， and gas-agent synergy for thermal front equilibrium. For thin heavy oil reservoirsthe steam absorption capacity and production ranges were improved through the thermal and horizontal well composite development model. For shallow extra-heavy oil reservoirs， HDNS technology was used to enhance the energy， reduce viscosity， and expand the spread， realizing efficient development. The application of development technologies for heavy oil reservoirs in Shengli Oilfield provides technical support for the beneficial development and green development of heavy oil in Shengli Oilfield.

Abstract:Shengli Oilfield has a large scale of undeveloped reserves，which is an important backup for the sustainable production of the oilfield. However，many years of development practice show that there are lots of problems in the overall development of these reserves，which restricts the economic development and production of the reservoir. In view of the characteristics of some reservoirs with low grade， difficult production， and poor development effect， the types and distribution characteristics of undeveloped reserves in Shengli Oilfield were systematically sorted out， and the main types of undeveloped reserves and key research objectives were defined. Based on the development practice in recent years in the reservoirs such as glutenites，beach bar sands，and deep lowpermeability heavy oil，the paper analyzed three main technologies for undeveloped reserves，including large-scale fracturing of wells with high inclination in glutenite reservoirs，pressure flooding in low-permeability beach bar sand reservoirs，and cold production of heavy oil reservoirs by chemical viscosity reduction. The large-scale fracturing technology of wells with long sections and high inclination combined engineering sweet spots and geological sweet spots through the geology and engineering integration，and its application in the glutenite oil reservoirs with low grade has greatly improved reservoir productivity. The innovative development concept of pressure-driven water injection technology has achieved a breakthrough in replenishing energy and increasing the production of beach bar sand reservoirs with low-permeability. The development technology of viscosity reduction combined with pressure flooding has achieved a breakthrough in the economic development of deep heavy oil reservoirs with low-permeability by changing the development idea. These three reservoir types have been effectively produced of undeveloped reserves from single well production，reservoir energy replenishment，and low-cost development and have achieved good development results. The breakthrough of development technologies and the change of development concept are the only ways for the effective development of undeveloped reserves，which has an important demonstration and guiding significance for the development of other undeveloped reserves in Shengli Oilfield.

Abstract:Shengli Oilfield has entered the middle and later development stages， and higher requirements for development seismic technologies have been set to develop reservoirs and further enhance oil recovery finely. The distribution and connectivity of conventional reservoirs in Jiyang Depression are complex due to different buried depths， multi-stage tectonic movements， various sedimentary types， and other factors. At the same time， constrained by seismic recognition， the well-seismic correspondences of some reservoirs are unclear， limiting the accuracy of fine reservoir characterization. In response to the development needs of different types of conventional reservoirs in Shengli Oilfield， a series of development seismic technologies have been formed through practice. These technologies include multi-method integrated reservoir prediction technology for middle and shallow fluvial facies reservoirs，integrated fine description technology for fracture systems in complex fault block reservoirs combing fine fault edge depiction and multiple attributes， prediction technology for middle-deep reservoirs with low permeability， and description technology of buried hill reservoirs fusing multiple parameters of“ fault-fracture-dissolution composite storage space.” These technologies provide strong support for reservoir development. However， as the target reservoirs for development get deeper，thinner，and smaller and expand into unconventional reservoirs， the development seismic technologies faces higher requirements and challenges. It is necessary to accelerate the integration process of processing and interpretation， strengthen the theoretical research of rock physics，promote the application of OVT domain pre-stack inversion in the description of multi-type oil reservoirs，tackle the fine description technologies of complex fault block-lithofacies reservoirs， break through the technical bottleneck of well-ground joint acquisition and gravitymagnetic-electric-seismic technology， and realize the application of artificial intelligence technology in the development seismic field，so as to further promote reservoir development.

Abstract:CO² capture，utilization，and storage （CCUS） can achieve a win-win situation of carbon emission reduction and oil production increase，and it is a key technology for the green and low-carbon transformation of the fossil energy industry. The petroleum and petrochemical industries have accelerated the large-scale application of CCUS technology after China proposed the goals of “peaking carbon emissions before 2030 and achieving carbon neutrality before 2060” in September 2020. It has gradually been revealed that CO² flooding has contradictions such as a low impact， short effective time，and rapid increase in the gas-oil ratio in the field practices of SINOPEC Shengli Oilfield and CNPC Jilin Oilfield. It is necessary to strengthen the optimization design of reservoir engineering further. This article systematically analyzed field practices of CO² flooding to enhance oil recovery in sandstone reservoirs in China and abroad and key issues in the optimization design of reservoir engineering，such as the matching between reservoir pressure maintenance level and miscible pressure，between well pattern direction and formation stress direction， between well spacing and reservoir permeability，and optimization of gas-water alternative displacement methods combined with the research results of the million-ton CCUS demonstration project in Shengli Oilfield. Then， the article summarized the latest progress in reservoir engineering research，such as reservoir pressure maintenance level during CO² flooding，well network，well spacing，and gaswater alternative displacement， and analyzed the increasing pressure method， well pattern， well spacing， and gas-water alternative displacement optimization design for high-pressure miscible flooding. Finally， it indicated that the research direction of CO² flooding reservoir engineering design should focus on the phase and flow laws of crude oil，CO²，and water in porous media under highpressure conditions， the synergistic mechanism of CO² flooding and storage，and the gas channeling mechanism of CO² flooding under complex reservoir conditions. This article provides technical support for large-scale CO² flooding in China.

Abstract:Underground natural gas storage is an essential infrastructure for strategic reserves， emergency peak shaving， and national energy security. It is also one of the directions for optimizing the industrial layout of mature oilfields and promoting green and low-carbon transformation and development. The geological conditions of Shengli Oilfield are complex， with shallow gas reservoirs，small scale， scattered distribution， and abundant oil and water trap resources. However， it is difficult to evaluate the sealing property. In view of these characteristics， significant progress has been made in research related to gas storage since the“ Thirteenth Five-Year Plan in 2016-2020” period. Different types of gas storage， such as loose sandstone gas reservoirs， gas cap oil reservoirs，and aquifers， have been studied and designed， and the first gas storage in abandoned water-flooded gas reservoirs in China， Y21 Gas Storage， has been built. Key technologies such as target screening and evaluation of gas storage in aquifers， injection and production operation optimization design of gas storage in aquifers， sealing evaluation of gas storage traps， and tracking evaluation of gas storage have been developed， which align with characteristics of Shengli Oilfield. At present， the construction of other types of gas storage still faces challenges such as limited data， small scale， poor efficiency， and difficulty in evaluating the dynamic sealing of traps. It is necessary to propose corresponding technical countermeasures and research directions in the site screening and evaluation of gas storage in oil reservoirs， the construction of gas storage in combination with scattered gas sand bodies， and the collaborative construction of gas storage in oil reservoirs with high water cut， to provide technical support for the large-scale construction and green development of gas storage in Shengli Oilfield.

Abstract:Reservoir numerical simulation technology is an important means of reservoir analysis， and it is a powerful tool for oilfield developers to design development schemes， proceed with dynamic tracking adjustment， and enhance oil recovery of reservoirs.In order to clarify the future development directions of reservoir numerical simulation technology in Shengli Oilfield，this paper reviewed the development process of reservoir numerical simulation application technology and independent intellectual property software in Shengli Oilfield over the past 60 years and summarized the innovative progress in numerical simulation application technology in many fields since the“ 13th Five-Year Plan in 2011-2015” period， which is applicable to current development and geological characteristics of Shengli Oilfield. The fields covered fine reservoir description in ultra-high water-cut stage， pressure flooding development in low-permeability reservoirs，heterogeneous combination flooding，multiple thermal combination flooding in heavy oil reservoirs， high-pressure CO2 miscible flooding， and integrated development of shale oil by large-scale fracturing. Then，this paper introduced the development and application of several reservoir numerical simulation software with Shengli characteristics，involving water flooding， chemical flooding， and micro and intelligent simulation. Finally， it was pointed out that under the current development situation of Shengli Oilfield， the reservoir numerical simulation is facing great challenges in terms of refinement，scale，efficiency，and collaboration approach， and the numerical simulation of reservoirs should be further developed towards integration，parallelization， and intelligence， so as to provide technical support for improving the quality and efficiency of Shengli Oilfield development.

Abstract:Shengli Oilfield is a typical continental compound oil and gas area with various reservoir types， many oil-bearing strata，and complex fault systems. It entered the extra-high water cut development stage with a water cut of more than 90% in the early 90s of the 20th century. The basis for enhanced oil recovery in mature oilfields with high water cuts is how to accurately characterize the changes of underground reservoirs and accurately recognize the remaining oil according to different types of reservoirs and development stages. To this end， the oilfield has carried out the fine reservoir description for the remaining oil potential in mature oilfields since 1996. A set of fine reservoir description technologies aligning with Shengli Oilfield characteristics has been formed through breakthroughs in critical technologies such as the fine characterization of reservoir architectures，fine description of low-sequence faults， phase division and connectivity evaluation of glutenites，prediction of thin beach dam sand reservoirs， three-dimensional geological modeling， and the fine description of the remaining oil，as well as multiple rounds of iterations of reservoir description technologies， and the technical specifications of fine reservoir description have been compiled. As of 2023，more than 600 development units have been described，covering 43.6 × 10⁸t of original oil in place. The modeling technology has been widely used in the adjustment of mature areas and the scheme preparation of new areas，which effectively supports the large-scale production of oilfields and stable production with benefits. This paper systematically analyzed the development process of reservoir description technologies in Shengli Oilfield， summarized the characteristic technologies of different types of reservoirs，analyzed five challenges faced by fine reservoir description in mature oilfields in the late stage of extra-high water cut，and expounded on five development directions of reservoir description technologies in the next step， which had guiding and reference significance for promoting fine reservoir description technologies in continental oilfields.

Abstract:As shale oil exploration and development intensifies， the experimental technologies for shale oil development have been continuously improved while inheriting the experimental technologies and methods of conventional reservoirs and shale gas reservoirs，and a set of experimental technology systems of reservoir physics and flow mechanisms has been initially formed，which provides strong technical support for geological evaluation of shale reservoirs，reservoir engineering optimization design，and enhanced oil recovery. The development status of six experimental technologies in China and abroad，including porosity，permeability，oil-water saturation，wettability，relative permeability， and imbibition，was systematically summarized. In view of the characteristics of continental shale oil， such as low maturity，strong heterogeneity，and well-developed lamina and micro-fractures，the measurement methods and principles， key influencing factors， control conditions of experiments， advantages and disadvantages and technical applicability of experiment methods were analyzed. The main problems， development trends， and research direction of these experimental technologies were put forward. The results show that ① unifying the cleaning agent and cleaning time of rock samples is the key to improving the comparability of different measurement methods of porosity， and nuclear magnetic resonance measurement of porosity is the technological development direction to meet the needs of rapid analysis in mining fields；② the irregular and multi-directional permeability measurement technology capable of simulating formation pressure changes is the future technological development direction；③ the alcohol soaking method and two-dimensional nuclear magnetic resonance （T₁-T₂） method are the technological development direction of the determination of shale oil-water saturation， but they still face the problem of the influence of clay bound water and adsorbed oil on the determination accuracy；④ the droplet morphology method is one of the future development directions of measurement technology of shale reservoir wettability，which requires further research and unified standards in experimental methods and comprehensive evaluation methods for surface wetting and spontaneous imbibition processes；⑤ the combination of experimental measurement and numerical method is an effective way to obtain the relative permeability of shale reservoirs， and the micro-oil and water metering， end-effect correction， as well as technologies and methods considering the time-varying pressure are the key directions；⑥ pressure imbibition measurement method should be used to evaluate imbibition effect and optimize well kill time in elastic development after fracturing. Pressure imbibition measurement methods based on nuclear magnetic resonance T₂spectrum， stratification T₂spectrum，and T₁-T₂spectrum will be one of the essential technological development directions.

Abstract:Shengli Oilfield has abundant chemical flooding resources. However，the implementation of chemical flooding technologies is difficult due to strong reservoir heterogeneity，high reservoir temperature， high formation water mineralization，high calcium and magnesium ion content，and high crude oil viscosity. After years of research and development， the theory of chemical flooding for high-temperature and high-salinity reservoirs has been established， forming a series of chemical flooding technologies such as polymer flooding， alkali-free binary compound flooding， heterogeneous compound flooding， and viscosity-reducing compound flooding. These technologies have significantly enhanced oil recovery in reservoirs with a formation temperature of 85 °C， a formation water mineralization of 30 000 mg/L，a calcium and magnesium ion concentration of 1 500 mg/L，and a crude oil viscosity of 1 000 mPa·s. In terms of basic theory，the mechanism of heterogeneous compound flooding was elucidated with“ deformation passage， fluid flow diversion，balanced displacement，and coordinated transfer and washing” to enhance oil recovery，and an essential understanding of“ simultaneously increasing viscosity and elasticity” and“ significantly reducing adhesion work” was obtained during chemical flooding in high-viscosity reservoirs. In terms of technical application，in response to the technical difficulties of significantly enhancing oil recovery in offshore oilfields，an efficient binary compound oil displacement system was constructed，and a fully enclosed injection process was designed，forming a binary compound flooding technology for offshore oilfields.For reservoirs after polymer flooding and high-temperature and high-salinity reservoirs，a viscoelastic particle oil displacement agents were invented，and a heterogeneous compound flooding system was constructed. In addition，heterogeneous compound flooding technology was developed. For high-viscosity reservoirs，highly viscoelastic polymers and efficient surfactants were developed， and a viscosity-reducing compound flooding system was constructed，forming an alkali-free binary compound flooding technology.As of October 2023，the chemical flooding technologies have achieved the produced geological petroleum reserve of 6.3 ×10⁸ t，an accumulated oil production of 7 701 × 10⁴ t，and an accumulated oil increase of 3 604 × 10⁴ t for high-temperature and high-salinity reservoirs in Shengli Oilfield，providing significant support for the sustained and high-quality development.

Abstract:Since the 1990s， Shengli Oilfield has integrated fluctuations in international oil prices， exploration and development trends， and technological advancements and developed a technical system for development planning that closely aligns with the strategic needs of each stage of oilfield development. Based on the practice of formulating mid-to-long-term development plans for Shengli Oilfield， this paper traced the evolution of development planning technologies in Shengli Oilfield and introduced the historical background， technical approaches， and challenges encountered by the development planning technologies during each stage.Through persistent research and practical application， the development planning technologies in Shengli Oilfield have progressed through four primary stages： scheme optimization， production planning， beneficial planning， and uncertainty planning. The development planning technologies developed during these stages have effectively supported the formulation of development planning strategies， guiding the oilfield’s development. With a focus on the sustainable development goals of Shengli Oilfield， it has been identified that there are three key issues for the development planning technologies to address： the challenge of mastering the economic principles of new field development， the need to reinforce the integration of mid-to-long-term planning with annual production schedules， and the requirement to elevate the strategic and forward-looking aspects of plans. In response to these challenges，the development planning technologies in Shengli Oilfield will prioritize uncertainty and multi-objective planning，alongside advancements in intelligence and precision， as well as strategic and futuristic development，so as to provide technical support for the strategic decision-making of oilfields.