Spontaneous imbibition is an important phenomenon in tight reservoirs. The existence of a large number fractures and micro-nano pores the key factor affecting spontaneous In this study, based on high-pressure mercury injection nuclear magnetic resonance experiments, pore distribution sandstone described. influence fractures, core porosity permeability, surfactants are studied by physical fracturing, interfacial tension test, wettability test experiments. results show that: radius...

Sedimentary facies identification is critical for carbonate oil and gas reservoir development. The traditional method of sedimentary not only be affected by the engineer's experience but also takes a long time. Identifying based on machine learning trend future development has advantages short time consuming reliable results without engineers' subjective influence. Although many references reported application to identify lithofacies, identifying reservoirs much more challenging due complex...

The characterization of two-phase flow has been commonly based on homogeneous wet capillary models, which are limited to heterogeneous porous media. In this work, pressure and relative permeability models for three systems derived, enable the analysis effect oil-wet ratio mechanism. pressures, permeabilities water cut curves simulated at primary drainage stage. results show that water-wet exhibit imbibition characteristics, respectively, while both these a large oil- is favourable oil...

This paper investigated fractal characteristics of microscale and nanoscale pore structures in carbonates using High-Pressure Mercury Intrusion (HPMI). Firstly, four different models, i.e., 2D capillary tube model, 3D geometry thermodynamic were used to calculate dimensions carbonate core samples from HPMI curves. Afterwards, the relationships between calculated petrophysical properties analysed. Finally, permeability model was predict then compared with Winland model. The research results...

Low-permeability oil and gas reservoirs have become one of the focuses exploration development worldwide, waterflooding is a cost-effective method that has been utilized to enhance recovery in such reservoirs. Since inevitable multiscale natural/artificial fractures micronano matrix pores, study for flow law fracture–matrix dual system becomes even more difficult. In this study, fractal characteristics porous media nonlinear behavior are taken into account derive similarity criteria; then,...

Abstract Considering capillary force, viscous and gravity buoyancy effects due to the oil–water density difference during imbibition process, a new mathematical model for core‐scale spontaneous considering is established. The rates with without in high‐, low‐, ultralow‐interfacial tension (IFT) solutions are compared. study shows that oil can accelerate rate, increasing core permeability decreasing IFT, differences rate become more significant. At high IFT of dozens mN/m, nonsignificant be...

Summary In our experiments, we investigated the effect of partial saturation on characteristic frequency and attenuation peaks for a tight sandstone by using stress-strain method at CNPC rock physics lab. The Young’s moduli sandstone, measured independently, were verified consistent reliable Kramers-Kronig approach. We studied variation P-wave velocity with different saturations peak which aimed obtaining frequency. meantime, normalized dispersion respect to 2 Hz as increase from 0% 100%...

Mercury injection capillary pressure analysis is a methodology for determining different petrophysical properties, including bulk density, porosity, and pore throat distribution. In this work, distinct parameters derived from mercury tests was considered the prediction of permeability by coupling machine learning theoretical approaches in dataset composed 246 tight sandstone samples. After quality checking dataset, feature selection carried out correlation models statistical with measured...

Abstract Well real-time flow rate is one of the most important production parameters in oilfield and accurate information crucial for monitoring optimization. With wide application permanent downhole gauge (PDG), high-frequency large volume temperature pressure make applying deep learning technique to predict possible. Flow well predicted with long short-term memory (LSTM) network using data. The specific LSTM neural are given, as methods data preprocessing training. developed model has been...

Earth and Space Science Open Archive This work has been accepted for publication in Journal of Geophysical Research - Solid Earth. Version RecordESSOAr is a venue early communication or feedback before peer review. Data may be preliminary. Learn more about preprints. preprintOpen AccessYou are viewing an older version [v1]Go to new version3D Tight Sandstone Digital Rock Reconstruction with Deep LearningAuthorsJiuyuZhaoiDFuyongWangiDJianchaoCaiSee all authors Jiuyu ZhaoiDChina University...

Summary Developing tight oil reservoirs is challenging due to ultra-low permeability and porosity. Oil recovery through spontaneous water imbibition into water-wet matrix an important mechanism of development. This paper develops a novel semi-analytical model for (SI) in with fractal theory. Firstly, pore structures sandstones were characterized geometry, space are assumed be bundles tortuous capillary tubes characteristics. Then, considering the boundary-layers initial residual oil, SI...

Summary The Ordovician carbonates of the Yingshan formation in Tarim Basin present a complicated pore structure due to diagenetic and secondary structures. Seismic elastic properties (e.g., velocity) depends on porosity as well structure. We estimated average specific surface, pore-throat radius, roundness, aspect ratio carbonate rocks from Tazhong area. Measuring results show that high P-wave velocity samples have small large ratio. Diversity dense result fluid-related variability. For or...

Summary In our experiments, we investigated the effect of brine on characteristic frequency and attenuation peaks for a reservoir sandstone. We observed two-attenuation which may be caused by combination two different fluid flow mechanisms. Two poroelatic models squirt mechanisms are used to investigate cause dispersion. Based these observations analysis, attribute modulus drained/undrained regime relaxed/unrelaxed regime.

Capillary pressure is an important parameter in both petrophysical and geological studies. It a function of different porous media properties, special, the pore structure rock. Mercury Injection Pressure (MICP) analysis consistent methodology for determining properties including porosity, throat distribution. The matrix permeability dependent on size distribution but not directly measured from MICP tests. In this work, we consider distinct parameters derived tests prediction by following...

Tight oil and gas reservoirs have attracted an increasing amount of attentions become one the focus research field in recent years. sandstones complex pore structures narrow pores throats with sizes varying from nanometers to micrometers, studying flow mechanisms tight is great importance oil/gas reservoir development. Reconstructing digital rock, which can comprehensively represent petrophysical properties sandstone, key simulating fluid micro/nanopores. This paper proposes a new method...