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Pore-scale analyses of heterogeneity and representative elementary volume for unconventional shale rocks using statistical tools

Fig. 6 Micro-CT image of Eagle Ford shale rock subsample L1R1N1 at resolution of 6.7 µm and physical extent of 1 mm × 1 mm × 1 mm. Subsample with a segmented three-dimensional CT images showing pores (red), organic matter(turquoise) and minerals (green), e.g. pyrite. b Segmented two-dimensional CT images showing pores (red), organic matter (turquoise) and minerals (green), e.g. pyrite.

In order to analyse the degree of heterogeneity, Eagle Ford parallel sample was further cropped into 96 subsamples. Descriptive statistical approach was then used to evaluate the existence of heterogeneity within the subsamples. Furthermore, the Eagle Ford parallel and perpendicular samples were analysed for volumetric entities representative of the petrophysical

Geometric Heterogeneity of Continental Shale in the Yanchang Formation, Southern Ordos Basin, China

Figure 8 Stratified lamina with various measurements.

These measurement tools correspond to the meter scale, decimeter scale, centimeter scale, millimeter scale and ten-micrometer scale, respectively, with measured thicknesses of 2.26 m, 2.09 dm, 1.70 cm, 1.48 mm and 11.70 μm, respectively. Fractal theory was used to analyze the power exponent distribution of the lamina thickness, with a resulting fractal dimension of 1.06.

Live Imaging of Micro-Wettability Experiments Performed for Low-Permeability Oil Reservoirs

Figure 5 (a–c) Elemental maps superimposed on a back-scatter electron image of the cryogenically-frozen middle Bakken sample after it had been submersed in formation oil. The elemental map in (a) is zoomed in (b) (green box, 30 µm wide) to reveal oil micro-droplets (green) in the intergranular space.

Live imaging of controlled water condensation/evaporation experiments allowed micro-droplet contact angles to be evaluated, while imaging combined with x-ray mapping of cryogenically frozen samples facilitated the evaluation of oil and water micro-droplet contact angles after successive fluid injection. For the first time, live imaging of fluids injected through a micro-injection

Kerogen Swelling and Confinement: Its implication on Fluid Thermodynamic Properties in Shales

Kerogen Swelling and Confinement, Its implication on Fluid Thermodynamic Properties in Shales

Abstract Type I kerogen was isolated from Green River Shale and characterized using SEM, TGA, DSC, and nitrogen adsorption. The swelling behavior of this kerogen with decane was analyzed using traditional test-tube swelling experiment and Dynamic Light Scattering. The TGA and DSC were used to analyze the thermodynamic behavior of decane

Model representations of kerogen structures: An insight from density functional theory calculations and spectroscopic measurements

Model representations of kerogen structures An insight from density functional theory calculations and spectroscopic measurements

Abstract Molecular structures of kerogen control hydrocarbon production in unconventional reservoirs. Significant progress has been made in developing model representations of various kerogen structures. These models have been widely used for the prediction of gas adsorption and migration in shale matrix. However, using density functional perturbation theory (DFPT) calculations and vibrational

Pore structure characterization of Chang-7 tight sandstone using MICP combined with N2GA techniques and its geological control factors

Pore structure characterization of Chang-7 tight sandstone using MICP combined with N2GA techniques and its geological control factors

Abstract Understanding the pore networks of unconventional tight reservoirs such as tight sandstones and shales is crucial for extracting oil/gas from such reservoirs. Mercury injection capillary pressure (MICP) and N2 gas adsorption (N2GA) are performed to evaluate pore structure of Chang-7 tight sandstone. Thin section observation, scanning electron microscope, grain size

Real-time detection of dielectric anisotropy or isotropy in unconventional oil-gas reservoir rocks supported by the oblique-incidence reflectivity difference technique

Real-time detection of dielectric in unconventional oil-gas reservoir rocks supported by the oblique-incidence reflectivity difference

Abstract Current geological extraction theory and techniques are very limited to adequately characterize the unconventional oil-gas reservoirs because of the considerable complexity of the geological structures. Optical measurement has the advantages of non-interference with the earth magnetic fields, and is often useful in detecting various physical properties. One key parameter that

Wellbore Stability in Oil and Gas Drilling with Chemical-Mechanical Coupling

Wellbore Stability in Oil and Gas Drilling with Chemical Mechanical Coupling

The relationships between shale mechanical parameters and the water content are established. The wellbore stability model chemical-mechanical coupling is obtained based on the experimental results. Under the action of drilling fluid, hydration makes the shale formation softened and produced the swelling strain after drilling. This will lead to the collapse

Analysis on Rock Properties Based on Exploration of Hole Wall’s Stability

Analysis on Rock Properties Based on Exploration of Hole Wall’s

Abstract Hole wall’s stability is a complex problem which exploration engineering has been working to solve. There are many reasons which may lead to hole wall’s instability. Aiming at hole wall’s stability in coal exploration, this paper takes shale as objects of study and uses the MPC method (for example: analyzing

New Rock-Eval Method for Characterization of Unconventional Shale Resource Systems

Unconventional resources such as tight, fractured and hybrid shale gas and oil plays as well as oil or kerogen shale systems, are considered exploitable self-contained source and reservoir rocks.Herein, we introduce a new “ready to use” method of analysis and interpretation for the Rock-Eval 6 device for better assessment of free or sorbed hydrocarbons in unconventional shale plays.

Abstract Unconventional resources such as tight, fractured and hybrid shale gas and oil plays as well as oil or kerogen shale systems, are considered exploitable self-contained source and reservoir rocks. A better understanding of the thermal cracking of sedimentary organic matter, hydrocarbons generation, expulsion, storage and retention mechanisms constitutes a key

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