The Hudson Oilfield’s Donghe sandstone reservoir has multiple independent oil–water systems. The complex oil–water relationship is mainly due to reservoir heterogeneity, especially the sealing and shielding effects of interlayers. T...
The Lunnan oilfield, nestled within the Tarim Basin, represents a prototypical extra-low-permeability sandstone reservoir, distinguished by high-quality crude oil characterised by a low viscosity, density, and gel content. The effective exploitation...
A large-scale sandstone-type uranium deposit, recently discovered within the petroleum field of the Jingchuan area on the southwestern margin of the Ordos Basin, exemplifies a classic case of uranium exploration success achieved through the analysis...
Fractal theory of particle size distribution (PSD) is a widely used approach in soil science. However, fractal studies on sandstone PSDs are scarce in sedimentology and geology. Taking littoral sandstones in the Carboniferous Donghetang Formation of...
Core samples of the tight sandstone reservoir in the Bonan Oilfield were analyzed by using multiple petrophysical experimental techniques, then a multi-scale three-dimensional digital rock model was constructed. The pore structure parameters of tight...
Polymer flooding is one of the most widely used and effective enhanced oil recovery techniques. It can improve the macroscopic sweep efficiency of a reservoir by controlling the fractional flow of water. The applicability of polymer flooding for one...
With the development of offshore oil fields, the reservoirs of X oilfield in the west of the South China Sea are poor in physical property, serious in pollution, and increasingly prominent in interlayer contradictions. Water injection dilation techno...
Hydraulic fracturing technology is vital for the efficient extraction of oil and gas from low-permeability tight sandstone reservoirs.Taking the central Bohai oilfield in China as an example, these fields are typically composed of thinly interbedded...
This study investigates the impact of CO2-enhanced oil recovery (CO2-EOR) on the petrophysical properties and oil recovery potential of sandstone reservoirs in the oilfields located in the east-southern Precaspian region of Kazakhstan. Despite the re...
As one of the most important and economically enhanced oil-recovery technologies, water flooding has been applied in various oilfields worldwide for nearly a century. Stratified water injection is the key to improving water-flooding performance. In w...
The water-flooded zone in a sandstone reservoir with a complex porosity–permeability relationship is difficult to interpret quantitatively. Taking the P Formation of Kalamkas Oilfield in Kazakhstan as an example, this paper proposed a reservoir...
In the observation of tight sandstone cores, the variations in the hydrocarbon charging usually can be observed in the same geological age reservoirs, which manifest as differential oil staining on the core surface. In order to clarify the micro tota...
With the continuous growth in global energy demand, research and development of unconventional oil and gas reservoirs have become crucial in the field of energy. This study focuses on the Chang 3 reservoir of the Yanchang Formation in the Ordos Basin...
The viscosity of crude oil plays a pivotal role in the exploration and development of oil fields. The predominant reliance on laboratory measurements, which are constrained by manual expertise, represents a significant limitation in terms of efficien...
Chemical flooding, such as alkaline-surfactant (AS) or nanoparticles-surfactant (NS) flooding, is an enhanced oil recovery (EOR) technique that has been increasingly utilized to enhance the oil production rate and recovery factor while reducing chemi...
At present, many offshore oil fields are facing problems, such as pollution-induced near-well zone blockage, poor inter-well connectivity, and strong vertical heterogeneity, which lead to insufficient formation energy and low production in the middle...
The Paleogene sandstone reservoir in the Huangtong Sag of the Fushan Depression is one of the most commercially prolific oil accumulations in the Beibuwan Basin, South China Sea. In this study, twenty-seven crude oil samples from four oilfields in th...
The sixth member of the Triassic Yanchang Formation (Chang 6 member) in the Dalugou area of the Jing’an Oilfield in the Ordos Basin is a typical ultra-low-permeability lithological reservoir. The Dalugou area has achieved some development progr...
Tight-sandstone oil and gas resources are the key areas of unconventional oil and gas resources exploration and development. Because tight-sandstone reservoirs usually have the characteristics of a low porosity and ultralow permeability, large-scale...
The seismic amplitude along a layer in a section can reveal lateral reservoir changes and is one of the important means of reservoir prediction, but it is often difficult to establish the quantitative relationship between the seismic amplitude and sa...
A method for evaluating the dominant seepage channel (DSC) water flooding in a layered sandstone reservoir is proposed and applied in an oilfield based on the water-cut derivative. The water-cut derivative curve of the reservoir with DSC shows double...
Owing to the heterogeneity of tight reservoirs, the development of fractures, and the unreasonable water injection development method, the logging response characteristics of water-flooded layers in fractured tight sandstone reservoirs in the H oilfi...
Oil and gas development is characterized by high technical complexity, strong interdisciplinarity, long investment cycles, and significant uncertainty. To meet the need for quick evaluation of overseas oilfield projects with limited data and experien...
The Sebei gas field is in the Sanhu depression area of the Qaidam Basin, which is the main gas-producing area and a key profit pillar for the Qinghai oilfield. The Sebei gas field within the Qinghai oilfield is characterized by high mud content, poor...
The complex fault block oilfields in the craton basin contain vast reserves of oil and gas resources. During the development of an oilfield, the flow of oil, gas, and water, is controlled by faults and configuration boundaries. The distribution of re...
Fracture network fracturing combined with oil–water infiltration and replacement is an effective approach to develop tight sandstone reservoirs. How to further improve oil recovery based on imbibition is a problem encountered during production....
After polymer flooding, the heterogeneity between different layers intensifies, forming intricate seepage channels and fluid diversions, which results in decreased circulation efficiency and lower recovery rates, leaving a significant amount of resid...
Tight sandstone reservoirs are ideal locations for CO2 storage. To evaluate the oil displacement efficiency and storage potential of CO2 in the tight sandstone reservoir in the Huang 3 area of the Changqing Oilfield, four kinds of displacement experi...
The Neogene Guantao Formation Reservoir in the PLOilfield is a unconsolidated sandstone with high porosity and high permeability. The reservoir diagenesis is weak and dominated by compaction diagenesis. At present, insufficient research into the rela...
Meandering river point bar sand bodies, serving as critical reservoir units, exhibit significant lithofacies heterogeneity that governs remaining oil distribution patterns. Taking the Guantao Formation in the Gudao Oilfield as an example, this study...
Previous studies performed in Abu Dhabi oilfields, United Arab Emirates, revealed the direct link of seismic wave attenuation to petrophysical properties of rocks. However, all those studies were based on zero offset VSP data, which limits the attenu...
As mature oilfields enter the high-water-cut development stage, significant amounts of residual oil remain trapped underground. To enhance the effectiveness of tertiary oil recovery, it is crucial to understand the distribution and mobilization patte...
Three-dimensional (3D) seismic data and well log data were used to investigate the sandstone architecture of the Middle Jurassic deltaic reservoirs of the Zhetybay Oilfield, Mangeshrak Basin, Kazakhstan. The base-level cycles of different scales were...
Offshore oilfields are characterized by loose sandstone reservoirs, strong heterogeneity and high injection and production intensity. Water channeling gradually develops after entering the high water cut stage, which weakens production performance. C...
The structure of caprocks is often greatly altered by different scales of faults or fissures in long-term geological tectonic evolution, and the sealing performance may be deteriorated. In this paper, a simplified geological model characterized as mu...
The lack of research on fine reservoir structure and sand body patterns in the Jidong Oilfield currently restricts the efficient development of the oilfield. Therefore, this article mainly focuses on the study of the main types of facies of the Shahe...
The high water cut period represents a critical phase in the development of tight oil wells, and accurately forecasting productivity during this stage is essential for effective oilfield development planning. However, traditional reservoir engineerin...
Tight gas reservoirs commonly occur in clastic formations having a complex pore structure and a high water saturation, which results in a threshold pressure gradient (TPG) for gas seepage. The micropore characteristics of a tight sandstone gas reserv...
The stability of nanoparticles at reservoir conditions is a key for a successful application of nanofluids for any oilfield operations, e.g., enhanced oil recovery (EOR). It has, however, remained a challenge to stabilize nanoparticles under high sal...
To clarify the characteristics of CO2–formation water–rock reactions in tight sandstones and their effects on CO2-enhanced oil recovery (EOR) efficiency and storage efficiency, this study takes the tight oil reservoirs of the Changqing Ji...
The primary factor constraining the performance of unconsolidated sandstone reservoirs is blockage from particle migration, which reduces the capacity of liquid production. By utilizing logging, seismic, core–testing, and oil–well product...
The transition zone between a shallow-water delta and tidal flat is characterized by a high degree of mixed siliciclastic–carbonate sedimentation. There are frequent lateral and vertical variations in sandstone, dolostone, limestone, and mixed...
Farnsworth Field Unit (FWU), a mature oilfield currently undergoing CO2-enhanced oil recovery (EOR) in the northeastern Texas panhandle, is the study area for an extensive project undertaken by the Southwest Regional Partnership on Carbon Sequestrati...
To solve the development problems caused by the geological characteristics of heterogeneous sandstone reservoirs, such as uneven interlayer exploitation, a method for improving uneven interlayer exploitation differences by applying interlayer injecti...
Geological storage is one of the most important measures to reduce carbon emissions. The newly developed oilfield A in the Pearl River Mouth Basin of the South China Sea is associated with a large amount of CO2 with a purity of up to 95%. Two weakly...
Addressing the poor performance of existing logging saturation models in low-permeability tight sandstone reservoirs and the challenges in determining model parameters, this study investigates the pore structure and fluid occurrence state of such res...
Fractured-porous carbonate reservoirs, mainly composed of dolomites and crystalline rocks with various rock types and extremely poor initial porosity and permeability, are dominated by tectonic fractures and exhibit extreme heterogeneity. The fractur...
Geothermal systems represent discrete and relatively homogenous habitats for extremophiles; investigation into the microbial community is key to revealing the geochemical environment and the geochemical evolution of fluids in geothermal reservoirs. T...
Hydraulic fracturing is a key stimulation technique for enhancing the productivity of tight sandstone reservoirs, with the conductivity of propped fractures serving as a critical parameter for evaluating stimulation effectiveness. This study investig...
This study presents a dual-layer GraphRAG framework for petroleum engineering question answering, in which instance-level facts and domain-level concepts are explicitly separated and integrated into retrieval-augmented generation. To evaluate the fra...
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