Anisotropic Rock Poroelasticity Evolution in Ultra‐low Permeability Sandstones under Pore Pressure, Confining Pressure, and Temperature: Experiments with Biot's Coefficient

Du, Shanshan

doi:10.1111/1755-6724.13886

Cited by 7 publications

(4 citation statements)

References 41 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The structural changes during maturation directly affect the mechanical properties of kerogen, such as microscopic pores and fracture mechanisms, and play a vital role in establishing oil/gas transport channels in shale oil/gas reservoirs. − However, kerogen exists at the nanoscale, and the mechanical properties through experiments are challenging to be measured. Therefore, molecular simulation is widely used to the mechanical properties of kerogen.…”

Section: Necessity Of Kerogen Molecular Modelmentioning

confidence: 99%

Perspectives of Machine Learning Development on Kerogen Molecular Model Reconstruction and Shale Oil/Gas Exploitation

Kang

Zhao

2022

Energy Fuels

View full text Add to dashboard Cite

The shale revolution has provided abundant shale oil/gas resources for the world, but the efficient, sustainable, and environmentally friendly exploitation of shale oil/gas is still challenging. Kerogen is the primary hydrocarbon source of shale oil/gas. The research on the kerogen chemo-mechanical properties significantly influences the development of shale oil/gas extraction technology. Rapid reconstruction of the kerogen molecular models is the most effective way to study the generation mechanism of shale oil/gas from the bottom-up molecular level. However, due to the combinatorial explosion problem, the reconstruction complexity of kerogen increases sharply because of the kerogen’s characteristics of complex origin, large molecular weight, and diverse functional groups. The traditional kerogen molecular reconstruction methods require professionals to comprehensively analyze various experimental information to approximate the actual kerogen molecular models through trial-and-error. So, the traditional methods are time and material-consuming and extremely inefficient. These shortcomings make researchers spend too much strength on the reconstruction of kerogen molecular models and cannot focus on the study of kerogen chemo-mechanical properties. For the past few years, state-of-the-art machine learning (ML) methods have been applied to intelligently reconstruct the kerogen molecular models through high-throughput and predict shale oil/gas production mechanisms. Although the current work is still in the infancy stage, ML methods are believed to be the most promising way to solve the drawbacks of traditional methods and reconstruct kerogen in reliable and large molecular weight. Hence, mechano-energetics is proposed to study the efficient development and utilization of energy based on mechanics and ML. This paper briefly reviews the development history of kerogen molecular model reconstruction methods and the research of ML in the fields of kerogen reconstruction and shale oil/gas exploitation. Some recommendations for further ML-based work are also suggested. We are convinced that the ML methods will accelerate the research of kerogen and promote the significant development of unconventional oil/gas exploitation technologies.

show abstract

Section: Necessity Of Kerogen Molecular Modelmentioning

confidence: 99%

Perspectives of Machine Learning Development on Kerogen Molecular Model Reconstruction and Shale Oil/Gas Exploitation

Kang

Zhao

2022

Energy Fuels

View full text Add to dashboard Cite

show abstract

“…The subcritical crack growth rate of the slick water2 group is lower than that of the slick water1 group, because the antiswelling agent added in slick water2 inhibits the osmotic hydration of rock clay minerals. Du et al (2021), observed that the hydration of strong hydrophilic clay minerals in water resulted in very strong surface adsorption reactions, thus could cause an increase in fluid bulk modulus. 24 Therefore, the degree of clay mineral hydration either due to the type of clay mineral or due to environmental conditions could lead to -0.12 -0.08 -0.04 0.00 0.04 0.08 0.12 0.16 0.20 0.24 increased stresses at the crack tip, and hence the observed difference in subcritical crack growth in different environments.…”

Section: Clay Swelling Effect On Subcritical Crack Growthmentioning

confidence: 99%

“…Du et al (2021), observed that the hydration of strong hydrophilic clay minerals in water resulted in very strong surface adsorption reactions, thus could cause an increase in fluid bulk modulus. 24 Therefore, the degree of clay mineral hydration either due to the type of clay mineral or due to environmental conditions could lead to -0.12 -0.08 -0.04 0.00 0.04 0.08 0.12 0.16 0.20 0.24 increased stresses at the crack tip, and hence the observed difference in subcritical crack growth in different environments. About 1.5% more antiswelling agents were added to slick-water group 2 than to group 1 solution.…”

Section: Clay Swelling Effect On Subcritical Crack Growthmentioning

confidence: 99%

Subcritical crack growth behavior of clay‐rich unconventional tight rocks under water‐saturated conditions

Yan

Huang

Muchiri

et al. 2022

Energy Science & Engineering

View full text Add to dashboard Cite

Hydraulic fracturing is the most widely used primary method for the stimulation of unconventional oil and gas resources. While knowledge of hydraulic fracture parameters is critical to reservoir productivity, predicting the fracture initiation is important for determining the complexity of the fracture network. Subcritical crack growth in reservoir rock plays an important role in forming fracture networks, but the understanding of the influence of fracturing conditions on subcritical crack growth is still lacking. In this paper, the subcritical crack growth behavior of sandstone and shale under ambient air, deionized (DI) water, and slick‐water conditions is studied. X‐ray diffraction analysis is done on the rock samples to determine their mineralogical composition, while tensile strength is measured by the Brazilian test. Then in Load Relaxation mode, a Double‐Torsion test (DT) is carried out under different conditions to study the subcritical crack growth of the samples. To further verify the influence of clay‐rich minerals, a similar analysis is performed on clay‐free granitic rock samples. The results of the tensile strength test and DT test demonstrate that the presence of clay minerals is the main reason for the difference in the subcritical crack growth behavior of shale and sandstone samples. DI water seems to better improve the subcritical crack growth compared with other test conditions. The value of the Subcritical Index (n) is smaller in a slick‐water environment than that in a DI water environment, revealing that slick water can better promote complex fracture propagation.

show abstract

“…However, for Chinese continental tight rock reservoirs, the porosity and permeability values are extremely low (porosity is about 10%, permeability is less than 0.3 × 10 −3 µm 2 ), and porosity testing is time-consuming. As a result, the accuracy of the test results decreases, causing logical inversion due to due to inaccurate flowmeter tests [34][35][36][37].…”

Section: The Concept Of "Two-dimensional Permeability"mentioning

confidence: 99%

Characterizing the Microscopic Anisotropic Permeabilities of Tight Oil Reservoirs Impacted by Heterogeneous Minerals

Wang

Wei

et al. 2022

Energies

Self Cite

View full text Add to dashboard Cite

This study aimed to reveal the anisotropic permeabilities of tight oil reservoirs impacted by heterogeneous minerals. SEM imaging, image processing, fractal calculation, microscopic reservoir modeling, and visual flow simulation were carried out to investigate the above problems. Results show that the variation coefficient of two-dimensional permeability for the studied tight reservoir samples ranges from 0.09 to 0.95, with an average value of 0.68. The penetration coefficient ranges from 1.16 to 2.64, with an average value of 2.13. The ratio of maximum to minimum permeability is between 1.25 and 7.67, with an average value of 5.62. The fluid flow in tight reservoirs has significant anisotropy comprising dominant flow through conductive channels. Flow in tight oil reservoirs tends to involve minor hydraulic fracturing with no proppant.

show abstract

Anisotropic Rock Poroelasticity Evolution in Ultra‐low Permeability Sandstones under Pore Pressure, Confining Pressure, and Temperature: Experiments with Biot's Coefficient

Cited by 7 publications

References 41 publications

Perspectives of Machine Learning Development on Kerogen Molecular Model Reconstruction and Shale Oil/Gas Exploitation

Perspectives of Machine Learning Development on Kerogen Molecular Model Reconstruction and Shale Oil/Gas Exploitation

Subcritical crack growth behavior of clay‐rich unconventional tight rocks under water‐saturated conditions

Characterizing the Microscopic Anisotropic Permeabilities of Tight Oil Reservoirs Impacted by Heterogeneous Minerals

Contact Info

Product

Resources

About