Topic Editors

School of Economics, Sichuan University of Science & Engineering, Yibin 644000, China
Kraków Institute of Geological Sciences, Jagiellonian University, Krakow, Poland
Dr. Shuai Yin
School of Earth Science and Engineering, Xi'an Shiyou University, Xi'an 710065, China

Geomechanics and Engineering Evaluation of Fractured Oil and Gas Reservoirs

Abstract submission deadline
31 January 2025
Manuscript submission deadline
31 March 2025
Viewed by
15485

Topic Information

Dear Colleagues,

The existence of reservoir fractures in oil and gas reservoirs not only improves the percolation performance of the reservoir but also controls the formation and distribution of the oil and gas. Fractures are widely distributed in tight carbonate rock, tight sandstone, mud shale and volcanic rock reservoirs. Fractured oil and gas reservoirs have become an important field for increasing oil and gas reserves and production and are also an important part of unconventional energy resources. Therefore, the development of reservoir geomechanics and engineering evaluation is an urgent need for the efficient development of this type of oil and gas reservoir. Because fractured reservoirs often have well-developed natural fractures, strong heterogeneity and anisotropy, and complex in situ stress distribution, it is difficult to carry out engineering and geological evaluation of fractured formations. At the same time, it brings major challenges to drilling and production, such as frequent leakage, wellbore instability, stuck pipes, low hydraulic fracturing conductivity, rapid water cut rise, and rapid production decline. In particular, the drilling safety accident caused by the instability of the wellbore severely restricts the exploration and development of oil and gas. The current research on geomechanics of fractured oil and gas reservoirs includes geological and engineering sweet spot prediction, pore-fracture coupling and evolution, quantitative characterization of natural fractures, in situ stress prediction and evaluation, coupling mechanism of natural fractures and artificial fractures, wellbore stability evaluation, hydraulic fracturing optimization, etc. These theoretical innovations and engineering practices provide support for drilling engineering in the development of fractured oil and gas resources, and provide feasible technical means and guarantees for increasing the rate of drilling in fractured formations and improving the efficiency of low-grade gas reservoirs. The theme of this Topic is to bring together original research and review articles discussing the research progress of the evaluation of geomechanics and engineering of fractured oil and gas reservoirs (tight carbonate rocks, tight sandstones, shale, volcanic rocks, etc.). We invite potential authors to discuss how to advance theoretical research and engineering applications such as pore–fracture coupling and quantitative characterization, natural fracture evolution and prediction, geomechanics, drilling and completion, and wellbore stability evaluation to further improve the exploration and development of fractured oil and gas reservoirs. Potential topics include, but are not limited to, the following:

  • Core elements and evaluation of reservoir geomechanics;
  • Formation, evolution mechanism, and controlling factors of pores and fractures;
  • Natural fracture prediction methods based on geology, logging, or seismic;
  • Coupling mechanism of natural fractures and artificial fractures;
  • Diagenetic evolution and classification of fractured reservoirs;
  • In situ stress distribution and quantitative evaluation of fractured reservoirs;
  • Drilling in fractured formations and evaluation of wellbore stability;
  • Prediction of geomechanical sweet spots in fractured reservoirs;
  • Hydraulic fracturing optimization of fractured oil and gas reservoirs;
  • Geomechanical changes caused by fluid–rock interactions in fractured reservoirs;
  • Engineering evaluation of fracturing fluids in efficient development of fractured reservoirs.

Dr. Hu Li
Dr. Ahmed E. Radwan
Dr. Shuai Yin
Topic Editors

Keywords

  • fractured reservoir
  • fracture characterization
  • geomechanics
  • engineering evaluation
  • sweet spot prediction
  • pore-fracture coupling
  • tight reservoir
  • diagenetic evolution
  • in-situ stress evaluation

Participating Journals

Journal Name Impact Factor CiteScore Launched Year First Decision (median) APC
Applied Sciences
applsci
2.5 5.3 2011 17.8 Days CHF 2400 Submit
Energies
energies
3.0 6.2 2008 17.5 Days CHF 2600 Submit
Geosciences
geosciences
2.4 5.3 2011 26.2 Days CHF 1800 Submit
Minerals
minerals
2.2 4.1 2011 18 Days CHF 2400 Submit
Remote Sensing
remotesensing
4.2 8.3 2009 24.7 Days CHF 2700 Submit

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Published Papers (10 papers)

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19 pages, 11018 KiB  
Article
Experimental Study on Pulsed Plasma Stimulation and Matching with Simulation Work
by Mina Khalaf, M. Soliman, S. M. Farouq-Ali, Craig Cipolla and Ron Dusterhoft
Appl. Sci. 2024, 14(11), 4752; https://doi.org/10.3390/app14114752 - 31 May 2024
Viewed by 256
Abstract
Plasma stimulation is a form of waterless fracturing as it requires that only the wellbore be filled with an aqueous fluid. The technique creates multiple fractures propagating in different directions around the wellbore. The intent of this paper is to present an experimental [...] Read more.
Plasma stimulation is a form of waterless fracturing as it requires that only the wellbore be filled with an aqueous fluid. The technique creates multiple fractures propagating in different directions around the wellbore. The intent of this paper is to present an experimental and numerical investigation of the degree of competitiveness of plasma stimulation with hydraulic fracturing, especially in the case of stimulating tight formation. Several cases were run experimentally. The samples included limestone and sandstone to investigate plasma fracturing in different rock types. In addition, the main goal of the experiments was to study the creation of fracture(s) under confining stresses, the type of rock, the amount of electrical energy used in the experiment, and the length of the wire to generate the plasma reaction. A laboratory plasma equipment was designed and used to accomplish the experimental work. The experiments were then numerically matched using a finite element numerical simulator, HOSS developed by LANL (Los Alamos National Lab). HOSS was developed to simulate high-strain-rate fractures such as those created by plasma stimulation. It accounts for mixed-mode fracture mechanics which are tensile and shear fractures. The simulator governing equations obey the conservation of mass and momentum in a solid-mechanics sense and account for the nonlinear deformation of rock material. The matching of the experiment allowed us to validate the HOSS simulation of the process and showed that the numerical results are in good agreement with the experimental work. Using the HOSS simulator, we also investigated the effect of higher energy levels and/or short release time on a cement rock model. The pressure profile that is developed due to the energy release can vary in the peak pressure and the release time. The results showed that the plasma fracturing technique is an effective stimulation method in sandstone and limestone. Plasma fractures were developed in the rock samples and extended from the sample wellbore to the outer boundaries. The shape of the pressure pulse has an impact on the developed fractures. Moreover, the effect of plasma stimulation on natural fractures was studied numerically. It was found that natural fractures can arrest the plasma-generated fractures that propagate from the wellbore to the outer boundaries. However, new fractures may develop in the rock starting from the natural fracture tips. Full article
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26 pages, 22374 KiB  
Article
Characteristics, Controlling Factors and Reservoir Quality Implications of Inner Fracture Zones in Buried Hills of Archean Covered Metamorphic Rock in Block 13-2, Bozhong Depression
by Junjie Lu, Xuanlong Shan, Jian Yi, Huiyong Li, Peng Xu, Guoli Hao, Ang Li, Shuai Yin, Shuyue Ren, Chaoyang Liu and Yunqian Shi
Energies 2024, 17(6), 1345; https://doi.org/10.3390/en17061345 - 11 Mar 2024
Viewed by 750
Abstract
Inner fracture zones play a decisive role in the formation of high-quality reservoirs in buried hill reservoirs in covered metamorphic rock. Based on core, sidewall core, thin section, seismic, logging and reservoir physical property data, the fracture development characteristics of the Bozhong 13-2 [...] Read more.
Inner fracture zones play a decisive role in the formation of high-quality reservoirs in buried hill reservoirs in covered metamorphic rock. Based on core, sidewall core, thin section, seismic, logging and reservoir physical property data, the fracture development characteristics of the Bozhong 13-2 block buried hill reservoir are described in detail and the controlling factors and the influence on reservoir quality are discussed. The results showed: (1) three groups of tectonic fractures developed in the study area—near-EW-striking, ENE-striking and nearly N–S-striking fractures—were controlled by the early Indosinian thrusting, the late Indosinian to early Yanshanian sinistral strike-slipping and the late Yanshanian late dextral strike-slipping in the Bohai Bay Basin, respectively. The ENE- and nearly-E-W-striking fractures are the most common, and the dip angles of the fractures are mostly between 35° and 75° and thus oblique. (2) The Indosinian-early Yanshanian was the main fracture-forming period, and the dextral strike-slip action in the late Yanshanian was the key to maintaining effective fractures. Imaging logging shows that 97.87% of the fractures are effective fractures. Based on thin section observation, 14.47% of the fractures are unmodified open fractures and 80.37% of the fractures are effective fractures due to reactivation. (3) The late Yanshanian strike-slip fault transformed the deformation adjustment zone formed by the early Indosinian thrust faulting and the core of the fold structure was more conducive to fracture development. The fracture density of a single well located within the deformation adjustment zone and at the core of the fold is between 0.93–1.49 m−1, the fracture density of a single well located only at the core of the fold is between 0.67–0.75 m−1 and that of a single well located at the wing of the fold is between 0.35–0.59 m−1. Diabase dike intrusions promoted the development of local fractures. (4) Fractures promote the migration and accumulation of oil and gas, and the fracture density in the oil layer is between 0.81–2.19 m−1. That in the nonoil layer is between 0.25–1.12 m−1. In addition, fractures not only provide storage space but also effectively improve the reservoir capacity of the inner fracture zones of buried hill reservoirs by concentrating dissolution. Full article
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23 pages, 7087 KiB  
Article
Paleotectonic Stress and Present Geostress Fields and Their Implications for Coalbed Methane Exploitation: A Case Study from Dahebian Block, Liupanshui Coalfield, Guizhou, China
by Jilin Wang, Youkun Wang, Xiaozhi Zhou, Wenxin Xiang and Changran Chen
Energies 2024, 17(1), 101; https://doi.org/10.3390/en17010101 - 23 Dec 2023
Cited by 1 | Viewed by 678
Abstract
The macroscopic structural fractures (joints) and geostress distribution characteristics of coal reservoirs are important factors affecting the exploitation of coalbed methane (CBM). In this study, the joints in the sedimentary strata of the Dahebian block in Liupanshui area, Guizhou Province were investigated. Directional [...] Read more.
The macroscopic structural fractures (joints) and geostress distribution characteristics of coal reservoirs are important factors affecting the exploitation of coalbed methane (CBM). In this study, the joints in the sedimentary strata of the Dahebian block in Liupanshui area, Guizhou Province were investigated. Directional coal samples were collected for observation and statistical analysis of coal microfractures, the paleotectonic stress fields of the study area were reconstructed, and the tectonic evolution was elucidated. The geostress distribution characteristics of the target coal seam (coal seam No. 11, P3l) in the study area were analyzed using the finite element numerical simulation method. The results indicate that the structural evolution of the Dahebian syncline in the study area can be divided into two stages. The Late Jurassic–Early Cretaceous stage (Early Yanshanian) is the first stage. Affected by the sinistral strike slip of the Weining–Ziyun–Luodian (WZL) fault zone, the derived stress field in the study area exhibits maximum principal stress (σ1) in the NEE–SWW direction. The Late Cretaceous stage (Late Yanshanian) is the second stage. Affected by the dextral strike slip of the WZL fault zone, the derived stress field exhibits σ1 in the NNW–SSE direction. The folds and faults formed in the first stage were modified by the structural deformation in the second stage. The dominant strikes of joints in the sedimentary strata are found to be in the NW–NNW (300°–360°) and NE (30°–60°) directions, with dip angles mostly ranging from 60° to 90°. The dominant strikes of coal microfractures are in the NW (285°–304°) and NE (43°–53°) directions. The distribution of geostress in the study area is characterized by high levels of geostress in the syncline center, decreasing towards the surrounding periphery. The overall trend of the geostress contour line is similar to the shape of the syncline and is influenced by folds and faults. The σ1 of coal seam No. 11 is vertical stress. The prediction results show that the joint density of coal seam No. 11 in the block is 36–50 joints/m, and the shape of the joint density contour line is also affected by the axial direction of the Dahebian syncline and the surrounding faults. The variation in coal seam joint density and the control effect of geostress on joints opening or closing affects the permeability of coal reservoirs. The study results provide significant guidance for the exploitation of CBM. Full article
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17 pages, 5246 KiB  
Article
Viscoelastic Strains of Palaeozoic Shales under the Burger’s Model Description
by Przemyslaw Michal Wilczynski, Jerzy Cieslik, Andrzej Domonik and Pawel Lukaszewski
Appl. Sci. 2023, 13(19), 10981; https://doi.org/10.3390/app131910981 - 5 Oct 2023
Cited by 1 | Viewed by 742
Abstract
This article presents the results of creep studies of Palaeozoic shales from the Baltic Basin in which the exploitation of shale gas in Poland was planned. Knowledge of instantaneous and long-term properties investigated in triaxial stress conditions is important from the point of [...] Read more.
This article presents the results of creep studies of Palaeozoic shales from the Baltic Basin in which the exploitation of shale gas in Poland was planned. Knowledge of instantaneous and long-term properties investigated in triaxial stress conditions is important from the point of view of exploitation techniques related to hydraulic fracturing. Rheological phenomena also play an important role in the analysis of the initial stress in shales, the knowledge of which is indispensable in the hydraulic fracturing process. The tests were carried out on samples representing four siltstone–claystone lithostratigraphic units occurring in the Baltic Basin. The studies and analyses were aimed at determining the character of creep in shales, selection of the appropriate rheological model for the analyzed rocks, and determination of the threshold of the linear creep under triaxial compression conditions. An original approach together with analysis results are presented here, which enable the separation and monitoring of shear and volume creep effects, and on this basis, the determination of the significance of the contribution of volume creep in the entire creep process. A relatively simple methodology for determination of the parameters of the Burgers model using this division is presented. The original value of the article is also due to the test results themselves and the parameter values of the analyzed model for triaxial creep of shales, which are not numerous in the literature. The investigations were performed at various loading levels in relation to the triaxial strength of the shales. Depending on the load, at its low values up to 0.7 (σ1σ3)max, creep had a determined character and did not show features of progressive creep. The linear creep threshold was also analyzed in this range. The loading level of 0.7 (σ1σ3)max was the limit of linear creep. Exceeding this load resulted in the loss of the linear character of creep, which in consequence lead to the subsequent third creep phase ending with rock damage. Parameters of the Burger’s model for gas shales from the Baltic Basin (northern Poland) were identified. There are significant differences in the behavior of shales depending on the lithostratigraphic unit from which the samples were collected. The mineral composition of the shales also influenced their behavior. Full article
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31 pages, 28254 KiB  
Article
Reservoir Characteristics and Development Model of Subaqueous Pyroclastic Rocks in a Continental Lacustrine Basin: A Case Study of the Chaganhua Subsag in the Changling Fault Depression, Songliao Basin
by Yunqian Shi, Jian Yi, Weihua Bian, Xuanlong Shan, Yuhu Liu, Guoli Hao, Ang Li, Qinglei Leng, Junjie Lu, He Pang and Ruichen Zhang
Energies 2023, 16(13), 4968; https://doi.org/10.3390/en16134968 - 26 Jun 2023
Viewed by 1355
Abstract
Industrial oil and gas eruptions underwater have been found in the pyroclastic rocks of the Huoshiling Formation in the continental lacustrine basin of the Changling fault depression, Songliao Basin. This paper investigates the reservoir space characteristics, physical characteristics, and pore structure differences of [...] Read more.
Industrial oil and gas eruptions underwater have been found in the pyroclastic rocks of the Huoshiling Formation in the continental lacustrine basin of the Changling fault depression, Songliao Basin. This paper investigates the reservoir space characteristics, physical characteristics, and pore structure differences of subaqueous pyroclastic reservoirs in the Huoshiling Formation, and the causes of physical property differences of different types of reservoirs and their formation and evolution processes are analyzed. (1) The content of volcanic glass in tuff is higher, the reservoir space is dominated by devitrification pores and dissolution pores, and the coarser the grain size, the more favorable the physical properties, with larger pore sizes and higher porosities. The content of clay minerals in sedimentary tuff is high, the pores between clay minerals are the main pores, and the physical properties of sedimentary tuff are poor. The content of soluble components such as feldspar, debris, and laumontite is high in tuffaceous sandstone, which is dominated by dissolution pores. (2) Primary pores are not developed in the pyroclastic reservoirs in the study area, and the reservoirs are relatively dense, with an average porosity of 2.43% and an average permeability of 0.076 mD. The coarse-grained tuff has the highest porosity, followed by tuffaceous sandstone and fine-grained tuff, and the sedimentary tuff has the least favorable physical properties. (3) Devitrification was an important cause of the high-porosity and ultralow permeability of tuff reservoirs. Two oil and gas charges in the middle diagenetic stage led to the organic acid dissolution of rocks. In addition, fractures can provide migration channels for organic acids and deep hydrothermal fluids, leading to late dissolution, and can connect various scattered dissolution pores to improve the effectiveness of the reservoir space. (4) Coarse-grained tuff reservoirs that developed in the proximal facies are favorable targets for hydrocarbon exploration. Full article
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26 pages, 6134 KiB  
Article
Effect of Sedimentary Facies Characteristics on Deep Shale Gas Desserts: A Case from the Longmaxi Formation, South Sichuan Basin, China
by Meng Wang, Jiang He, Shu Liu, Chunlin Zeng, Song Jia, Zhou Nie, Shengxiu Wang, Wei Wang and Chun Zhang
Minerals 2023, 13(4), 476; https://doi.org/10.3390/min13040476 - 28 Mar 2023
Cited by 2 | Viewed by 1605
Abstract
Shale gas is one of the hot spots of energy development. Due to the strong heterogeneity and low physical properties of shale gas reservoirs, and the complex influencing factors of pore development, it is necessary to conduct a comprehensive analysis of the control [...] Read more.
Shale gas is one of the hot spots of energy development. Due to the strong heterogeneity and low physical properties of shale gas reservoirs, and the complex influencing factors of pore development, it is necessary to conduct a comprehensive analysis of the control factors of high-quality reservoirs. The sedimentary characteristics, mineral composition, pore structure and controlling factors of high quality reservoir development are studied on the basis of thin section, scanning electron microscopy (SEM) and QEMSCAN analysis, X-ray diffraction (XRD), total organic carbon (TOC), Nano-CT scanning and Low-pressure N2 adsorption (N2GA) analysis on shale samples from the Longmaxi Formation in South Sichuan Basin. The results show the following: (1) According to lithology, sedimentary structure, organic carbon content and mineral composition, six sedimentary microfacies can be divided. (2) Organic matter pores are developed in organic-rich siliceous shale and organic-rich silty shale at the bottom of the first member of the Longmaxi formation, with average porosity of more than 5% and permeability of more than 2 × 10−3 μm2, which is conducive to the formation of high-quality shale gas reservoirs. (3) The contents of siliceous and TOC are positively correlated with porosity and specific surface area, while the contents of carbonate and clay minerals are negatively correlated with reservoir quality. (4) In the first member of the Longmaxi formation, the sedimentary water depth becomes shallower from bottom to top, and the sedimentary environment changes from a reduction to an oxidation environment. The contents of siliceous and organic matter decrease, while the contents of clay minerals and carbonate minerals show the opposite trend. The difference in sedimentary microfacies affects the distribution of mineral and organic matter and controls the heterogeneity of the shale reservoir. Full article
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12 pages, 5189 KiB  
Article
The Role of Fluid Overpressure on the Fracture Slip Mechanism Based on Laboratory Tests That Stimulating Reservoir-Induced Seismicity
by Yujie Zhu, Chen Xu, Danqing Song, Xiaoli Liu and Enzhi Wang
Appl. Sci. 2023, 13(6), 3382; https://doi.org/10.3390/app13063382 - 7 Mar 2023
Viewed by 1137
Abstract
A critically stressed fracture will slide in response to the increase in fluid pressure inside the fracture while impounding, which will trigger induced seismicity. The mechanism of fluid overpressure is regarded as a significant factor in the reaction of the fracture slip after [...] Read more.
A critically stressed fracture will slide in response to the increase in fluid pressure inside the fracture while impounding, which will trigger induced seismicity. The mechanism of fluid overpressure is regarded as a significant factor in the reaction of the fracture slip after water diffusing. This study uses a shearing test with a cylinder of granite, with 100 mm height and 50 mm diameter, under the condition of hydraulic-mechanic (HM) coupling to figure out how fluid overpressure alters the mechanical behavior of the critically stressed fracture. The cyclic water pressurization simulates periodical impounding in the water reservoir. Results show that several slip events happen when water pressure continues to rise higher than the stable state. The change of roughness also indicates the deterioration of the fracture surface while sliding. According to the results, we conclude that the difference between inlet pressure and outlet pressure leads to an overpressure of the fracture, promoting a series of slips and induced seismicity. Hydraulic energy is introduced to explain the relationship between the input and output energy, which is also strong evidence to illustrate that fluid overpressure is a crucial mechanism in reservoir-induced seismicity. Full article
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16 pages, 6023 KiB  
Article
Evaluating the Degree of Tectonic Fracture Development in the Fourth Member of the Leikoupo Formation in Pengzhou, Western Sichuan, China
by Qiang Xie, Gao Li, Xu Yang and Hongli Peng
Energies 2023, 16(4), 1797; https://doi.org/10.3390/en16041797 - 11 Feb 2023
Cited by 2 | Viewed by 1955
Abstract
The extent of fracture development is associated with the degree of enrichment of a natural gas reservoir and its productivity. Based on numerical simulation results of the paleotectonic stress field, a set of evaluation methods for determining the degree of development of reservoir [...] Read more.
The extent of fracture development is associated with the degree of enrichment of a natural gas reservoir and its productivity. Based on numerical simulation results of the paleotectonic stress field, a set of evaluation methods for determining the degree of development of reservoir tectonic fractures were established using rock rupture criteria. Taking the fourth member of the Leikoupo Formation in the Pengzhou area of western Sichuan as an example, a finite element (FE) method was employed to simulate the paleo-tectonic stress field during the period of fracture development, and the degree of tectonic fracture development was further evaluated using the above methods. The results indicated that effective fractures were created in the Himalayan period. In this time, mainly NE–NEE and nearly E–W strike tectonic fractures were developed in the target layer. The fractures were mainly low-angle and oblique fractures, while the high-angle fractures were less developed. According to the integrative fracture index (F), five typical fracture development areas were determined: the fault zone, and the northern, eastern, southeastern, and central regions of the study area. The reliability of the fracture prediction results was verified using fracture distribution statistics and gas production test results. Full article
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21 pages, 8765 KiB  
Article
Reservoir Characteristics and Their Controlling Factors in Siliceous Shales of the Upper Permian Dalong Formation, Western Hubei Province, South China
by Ke Duan, Tong Xie, Yi Wang, Yanlin Zhang, Wanzhong Shi and Yongchao Lu
Appl. Sci. 2023, 13(3), 1434; https://doi.org/10.3390/app13031434 - 21 Jan 2023
Cited by 1 | Viewed by 1426
Abstract
To evaluate the reservoir characteristics of siliceous shale in the Dalong Formation within the late Permian intra-platform rift trough in Western Hubei (China), we studied a drill core from well ED-2 in Western Hubei. To analyze the physical characteristics, pore structure, methane adsorption [...] Read more.
To evaluate the reservoir characteristics of siliceous shale in the Dalong Formation within the late Permian intra-platform rift trough in Western Hubei (China), we studied a drill core from well ED-2 in Western Hubei. To analyze the physical characteristics, pore structure, methane adsorption performance, and their influences on the siliceous shale reservoir, we performed X-ray diffraction, total organic carbon (TOC) content, vitrinite reflectance (Ro, indicating thermal evolution), total porosity and permeability, field emission scanning electron microscopy, CO2 and N2 physical adsorption, and methane isothermal adsorption analyses, among others. Our results show that the Dalong Formation in Western Hubei is an organic-rich (2.6–14.3 wt.%), highly thermally evolved (Ro = 2.59–2.76%), siliceous shale containing mainly type-I and type-II1 organic matter. The Dalong siliceous shale has low porosity and permeability and belongs to a larger reservoir with low horizontal permeability (0.002–335.209 mD) and porosity (1.2–7.8%). Pores in the shale are mainly organic, inorganic, and microfractures; the organic pores are very developed. The pore volume and specific surface area of the shale are mainly due to micropores and mesopores and are positively correlated with TOC and clay mineral contents and weakly negatively correlated with quartz and carbonate contents. The micropores and mesopores are well developed, improving the methane adsorption capacity, which, in turn, is strongly positively correlated with TOC content. Comprehensive analysis shows that the high organic matter content of the Dalong siliceous shale has the greatest influence on its pore structure; the many organic pores generated after hydrocarbon generation have controlled the development of micropores and mesopores, which is conducive to the adsorption and storage of shale gas. The development of brittle minerals resistant to compaction, such as siliceous minerals, helps preserve organic pores. This study is informative for basin-scale petroleum system investigations, which are essential for understanding oil and gas exploration possibilities and regional petroleum systems. Full article
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15 pages, 4830 KiB  
Article
Expansive Soil Stabilization with Lime, Cement, and Silica Fume
by Ahmed S. A. Al-Gharbawi, Ahmed M. Najemalden and Mohammed Y. Fattah
Appl. Sci. 2023, 13(1), 436; https://doi.org/10.3390/app13010436 - 29 Dec 2022
Cited by 19 | Viewed by 3542
Abstract
The type of soil known as expansive soil is capable of changing its volume through swelling and contracting. These types of soils are mostly composed of montmorillonite, a mineral with the capacity to absorb water, which causes the soil to heave by increasing [...] Read more.
The type of soil known as expansive soil is capable of changing its volume through swelling and contracting. These types of soils are mostly composed of montmorillonite, a mineral with the capacity to absorb water, which causes the soil to heave by increasing its volume. Due to their capacity to contract or expand in response to seasonal fluctuations in the water content, these expansive soils might prove to be a significant risk to engineering structures. Many studies have dealt with swelling soils and investigated the behavior of these soils, as well as their improvement. In this study, three percentages of lime, cement, and silica fume (5, 7, 9%) are used to stabilize the expansive soil, and the work is divided into two sections: the first is using a consolidation test to record the free swell and swell pressure for the untreated and treated soils; in the second part, the grouting technique is utilized as a process that can be applied in the field to maintain the improvement in the bearing capacity. It is concluded that the soil stabilized with different percentages of lime, cement, and silica fume exhibits a decrease in both free swell and swelling pressure by approximately 65% and 76%, respectively, as compared with untreated soil. The soil grouted with silica fume increases the bearing capacity of footings resting on the grouted soil by approximately 64% to 82% for the soil treated with 5% and 9% silica fume, respectively, as compared with untreated soil. Full article
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