It is well known that underground in situ pyrolysis technology for oil shale production is a promising field. In the in situ modification mining process, the permeability property of a shale matrix has a great effect on the transport capacity of pyro...
Microscopic flow in fractured porous media is a typical problem for the exploitation of tight reservoirs. The rapid-flow in the fractured porous-media is of great significance to efficient and continuous oil/gas exploitation. The fractures are expect...
Most hydrate-bearing sediments worldwide exhibit mixed pore- and fracture-filling hydrates. Due to the high exploitation value, pore-filling hydrate production is the focus of current hydrate production research, and there is a lack of systematic res...
Coal is a complex heterogeneous and anisotropic material conformed with fractal characteristics. The pore and fracture characteristics have important influence on the dynamic disasters including rock burst and gas outburst, however, the relationship...
This work focused on the nonlinear seepage behaviors of flow in pore-fracture media. Natural sandstones were selected to prefabricate single-fracture specimens with different inclinations (0–90°). Seepage tests of combined media were performed under...
The connectivity of the internal pores and fractures in oil shale is the critical factor in determining the success of the insitu pyrolysis of the oil shale with superheated steam. In this paper, using a self-developed superheated steam pyrolysis exp...
Pore structure heterogeneity of coal reservoirs restricts the diffusion-seepage process of coalbed methane, thereby restricting the production capacity of coalbed methane. Therefore, 10 coal samples from the Linxing area are taken as an objective, an...
We propose three idealized hydraulic fracture geometries (“fracture scenarios”) likely to occur in shale oil reservoirs characterized by high pore pressure and low differential in situ stresses. We integrate these geometries into a commercial reservo...
The Forchheimer equation is widely used in studying non-Darcy flow. Non-Darcy flow coefficient β in the Forchheimer equation is generally thought to be positive, and there are few studies on negative values. In this work, we performed seepage te...
To achieve an accurate and comprehensive characterization of the multiscale pore–fracture characteristics of Permian coal in the Jingbian Block, Ordos Basin, a combination of scanning electron microscopy (SEM), X-ray computed tomography (CT), a...
Studying the heterogeneity of coal reservoirs is significant to coal bed methane (CBM) exploitation. To investigate the development of the pore–fracture and acoustic emission response characteristics of the coal rock in the Yunnan Laochang bloc...
The instability and failure of coal pillars is one of the important factors leading to the catastrophic consequences of coal mine goaf collapse. Coal mine water has the characteristics of high salinity. Long-term mine water erosion can easily deform...
Deep coalbed methane (CBM) demonstrates significant production potential, and a fervent exploration and development boom is currently underway in China. The permeability of coal reservoirs is heavily influenced by pore–fracture structure hetero...
Pore and fracture structure heterogeneity is the basis for coalbed methane production capacity. In this paper, high-pressure mercury intrusion test curves of 16 coal samples from the Taiyuan Formation in the Linxing area are studied. Based on the fra...
The tectonically deformed coal (TDC) reservoirs with abundant gas resources and low permeability are expected to become one of the target coal seams for carbon dioxide geological storage-enhanced coalbed methane recovery (CO2-ECBM). The pore–fr...
The pore structure of reservoir rocks was a crucial factor affecting hydrocarbon production. Accurately characterized the micropore structure of different types of rock reservoirs was of great significance for unconventional natural gas exploration....
This study examines the distribution of pore pressure (PP) and fracture gradient (FG) within intervals of lost circulation encountered during drilling operations in the Ordovician reservoir (IV-3 unit) of the Tin Fouye Tabankort (TFT) field, located...
A coupled numerical approach is used to evaluate the influence of pore connectivity and microcracks on leaching kinetics in fully saturated cement paste. The unique advantage of the numerical model is the ability to construct and evaluate a material...
In this paper, the influence of micro-fractures on the flow of tight reservoirs is studied on the microscopic scale. Three-dimensional digital cores of fractured tight sandstone with varying fracture apertures, lengths, and dip angles are constructed...
Hydraulic fracturing technology significantly enhances the productivity of shale oil and gas reservoirs. Nonetheless, the infiltration of fracturing fluid into shale formations can detrimentally affect the microscopic pore structure, thereby impairin...
Gulong shale oil is found in a typical continental shale oil reservoir, which is different from marine shale oil reservoirs. The Gulong shale oil reservoir is a pure shale-type oil reservoir with abundantly developed nanoscale pores, making it extrem...
Based on the uniaxial compression tests and in situ CT scanning experiments of lignite with different dehydration times and the fractal theory, this paper qualitatively and quantitatively investigated the influence of the dehydration effect on the ev...
Pore structure has been widely observed to affect the seismic wave velocity of rocks. Although taking lab measurements on 1.0-inch core plugs is popular, it is not representative of the fractured-vuggy carbonates because many fractures and vugs are o...
The pore-fractures network plays a key role in coalbed methane (CBM) accumulation and production, while the impacts of coal facies on the pore-fractures network performance are still poorly understood. In this work, the research on the pore-fracture...
CO2 pre-injection fracturing is a promising technology for shale reservoirs development, with multiple advantages for improving the complexity of fractures, the production of crude oil, and the sequestration of CO2. Previous research mostly focused o...
In this paper, 12 sandstone samples are collected from the Taiyuan Formation in Qinshui Basin, and sample types using the T2 spectral under LF-NMR saturation and centrifugation conditions are classified. Moreover, single and multifractal models were...
The purpose of the current study is to propose a novel meta-heuristic image analysis approach using multi-objective optimization, named ‘Pixel-wise k-Immediate Neighbors’ to identify pores and fractures (both natural and induced, even in...
Heterogeneity of pore and fracture structures has become an important factor affecting the migration of methane and water in coal reservoirs. However, controlling factors of pore and fracture structure collected from coal seam 10 in Taliqike Formatio...
Unconventional oil and gas resources are indispensable, and shale oil is one of them. The Junggar Basin is a typical superposition oil and gas basin in China, with reserves of 100 million tons in many areas and various types of oil and gas reservoirs...
Coal permeability is related to the fracture-pore structure of coal and is a key factor in determining gas drainage efficiency. The characteristics of the methane flow in coal fractures are different from those in coal matrix pores. However, due to t...
Viscoelastic surfactant (VES) fluid and hydrolyzed polyacryamide (HPAM) solution are two of the most common fracturing fluids used in the hydraulic fracturing development of unconventional reservoirs. The filtration of fracturing fluids in porous med...
The deep coal seams in the southern Sichuan region contain abundant coalbed methane resources. Determining the characteristics and distribution patterns of coal structures in this study area, and analyzing their impact on pore and fracture structures...
Gas prevention and control have always been the focus of coal mine safety. The pore structure characteristics and gas adsorption characteristics of coal seams are the key factors affecting gas adsorption and diffusion in coal seams. Lvjiatuo Mine has...
Research has delved into the main controlling factors for the evolution of the pore-fracture structure in deep coal samples. The gas content is influenced by multiple factors, among which the pore-fracture structure in deep coal samples stands as one...
Pore–fracture carbonate gas reservoirs exhibit complex pore–throat structures and significant heterogeneity. Formation water can easily migrate along fractures, leading to extensive water-sealed gas accumulation, which severely limits the...
This study systematically investigates the pore–fracture architecture of deep coal seams in the JiaTan (JT) block of the Ordos Basin using an integrated suite of advanced techniques, including nuclear magnetic resonance (NMR), high-pressure mer...
The study of pore structure in low-permeability sandstone uranium deposits has become a key factor in the profitability of uranium mining. In this paper, pore and fracture distribution in the target sandstone were determined by using mercury injectio...
Pore structure heterogeneity affects the porosity and permeability variation of tight sandstone, thereby restricting sandstone gas production. In total, 11 sandstone samples were taken as a target in the northwest margin of the Junggar Basin. Then, s...
Rock fracture is a macroscopic fracturing process resulting from the initiation and propagation of microscopic cracks. Therefore, it is crucial to comprehend the damage and fracture mechanism of rock under ultrasonic vibration by investigating the ev...
Many studies have used fractal theory to characterize pore structure distribution heterogeneity through mercury intake curves. However, there is relatively little research on the fractal model calculation of mercury removal curves. In this study, a h...
Many studies have shown that the thermal evolution degree is the main factor affecting the micropore structure of coal reservoirs. However, within the same thick coal seam, the Ro,max of the entire coal seam is not much different, which affects the d...
Hydraulic fracturing is widely used for developing shale reservoirs with low porosity and permeability. Large volumes of fracturing fluids are injected into reservoirs, yet the impact of these fluids on shale is not entirely understood. This study in...
Hydraulic fracturing significantly impacts water production. This makes it crucial to determine whether its effects on formation water production are beneficial or detrimental in complex reservoir stimulations. This paper gives the influence that act...
Volcanic rock reservoirs for oil and gas are known worldwide for their considerable heterogeneity. Micropores and fractures play vital roles in the storage and transportation of natural gas. Samples from volcanic reservoirs in Songliao Basin, CS1 and...
The characteristics of CO2 seepage in reservoirs have important research significance in the field of CCS technology application. However, the characteristics of macro-scale seepage are affected by the geometrical characteristics of micro-scale media...
Indirect fracturing from roof rock to coal using a horizontal well is a new and promising technology for coalbed methane surface exploitation in soft and low-permeability coal seams. In order to study the propagation law of hydraulic fractures across...
Currently, microscopic research on the tensile fracture properties of recycled brick coarse aggregate concrete has mainly adopted microscopy techniques, which can clearly observe the actual damage situations of each phase material but are unable to i...
A fractal discrete fracture network based model was proposed for the gas production prediction from a fractured shale reservoir. Firstly, this model was established based on the fractal distribution of fracture length and a fractal permeability model...
Tight sandstone reservoirs, as typical unconventional reservoirs, have attracted more and more attention worldwide. Compared to conventional reservoirs, the complex microscopic pore structures and micro-fractures of the tight reservoirs are developed...
Coal resource extraction and utilization are essential for sustainable development and economic growth. This study integrates a pseudo-triaxial mechanical loading system with low-field nuclear magnetic resonance (NMR) to enable the preliminary visual...
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