To see the other types of publications on this topic, follow the link: Microfractura.
Journal articles on the topic 'Microfractura'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Microfractura.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Sánchez, Santana Ulises, Gerardo Presbítero-Espinosa, and José María Quiroga-Arias. "Aplicación de análisis de microfracturas para prevención de fracturas por fatiga en materiales mediante pruebas no destructivas." Revista Latinoamericana de Difusión Científica 6, no. 11 (2024): 87–111. https://doi.org/10.5281/zenodo.12687168.
Full textAbstract:
<em>Objetivo</em>: Determinar, establecer y verificar metodologías y campos de estudio hacia procedimientos de predicción precisos para la prevención de fracturas por fatiga en materiales industriales, mediante el desarrollo de microfracturas y el uso de ensayos no destructivos. <em>Metodología</em>: Se implementan ensayos de fatiga en materiales de uso industrial, utilizando máquinas de ensayo mecánicas universales capaces de realizar esfuerzos de fatiga. En cuanto al uso de equipos de análisis no destructivo, se utilizó un sistema de tomografía computarizada de rayos X para estudiar microfracturas en materiales. La detección de microfracturas se realizó mediante procesamiento de imágenes con una red neuronal convolucional entrenada mediante aprendizaje profundo. Posteriormente, se aísla la microfractura mediante procesamiento de imágenes. Las imágenes que contienen esta característica se interpretan mediante procesamiento de imágenes para obtener sus métricas de área, perímetro, longitud de la característica, circularidad, orientación y tipo de microfractura. <em>Resultados</em>: Hemos sentado las bases para un campo de estudio completamente nuevo e innovador para futuros modelos de prevención de fracturas por fatiga en una evaluación tridimensional de microdaños, en el que incluso un concepto de volumen característico novedoso puede proponerse y usarse para procedimientos y enfoques adicionales hacia la prevención de la fatiga.
2
Wang, Muyuan, Keliu Wu, Qingyuan Zhu, and Jiawei Ye. "Unveiling the Impact of Microfractures on Longitudinal Dispersion Coefficients in Porous Media." Processes 13, no. 3 (2025): 722. https://doi.org/10.3390/pr13030722.
Full textAbstract:
Longitudinal dispersion coefficient is a key parameter governing solute transport in porous media, with significant implications for various industrial processes. However, the impact of microfractures on the longitudinal dispersion coefficient remains insufficiently understood. In this study, pore-scale direct numerical simulations are performed to analyze solute transport in microfractured porous media during unstable miscible displacement. Spatiotemporal concentration profiles were fitted to the analytical solution of the convection–dispersion equation to quantify the longitudinal dispersion coefficient across different microfracture configurations. The results indicate that the longitudinal dispersion coefficient is highly sensitive to microfracture characteristics. Specifically, an increased projection length of microfractures in the flow direction and a reduced lateral projection length enhance longitudinal dispersion at the outlet. When Peclet number ≥1, the longitudinal dispersion coefficient follows a three-stage variation pattern along the flow direction, with microfracture connectivity and orientation dominating its scale sensitivity. Furthermore, both diffusion-dominated and mixed advective-diffusion regimes are observed. In diffusion-dominated regimes, significant channeling alters the applicability of traditional scaling laws, with the relationship between longitudinal dispersion coefficient and porosity holding only when the Peclet number is below 0.07. These results provide a comprehensive scale-up framework for CO2 miscible flooding in unconventional reservoirs and CO2 storage in saline aquifers, offering valuable insights for the numerical modeling of heterogeneous reservoir development.
3
Hidalgo Acosta, Javier Aquiles, Eduardo Luis Esquivia Martínez, Juan Carlos Briones Olvera, et al. "Lesiones osteocondrales de rodilla por sobreuso en adultos, técnicas quirúrgicas terapéuticas actuales. Reporte de dos casos clínicos." Mediciencias UTA 7, no. 1 (2023): 76–83. http://dx.doi.org/10.31243/mdc.uta.v7i1.1935.2023.
Full textAbstract:
Introducción Las lesiones osteocondrales de rodilla consisten en una anomalía localizada que afecta la médula subcondral, el hueso subcondral y el cartílago articular, son un desafío clínico, principalmente en pacientes jóvenes. Los dolores que presentan este grupo de pacientes afectan grandemente su calidad de vida, limitando su actividad física y desarrollo osteomuscular. Actualmente existen técnicas quirúrgicas que pueden remediar estos trastornos, mejorando el estilo de vida de los pacientes. Objetivos: describir dos casos clínicos de lesiones osteocondrales de rodilla por sobreuso en adultos, y determinar las técnicas quirúrgicas terapéuticas más actuales. Materiales y métodos: Se realiza un estudio descriptivo, retrospectivo para presentación de casos clínicos, se obtiene consentimiento informado del departamento de docencia e investigación, para revisión de historia clínica e imágenes que serán utilizadas en la publicación de este trabajo. Discusión: se presentan dos casos clínicos de pacientes que desarrollan lesiones osteocondrales de rodilla, que son diagnosticados e intervenidos quirúrgicamente mediante realización de artroscopia en rodilla afecta, y cuyos resultados a largo plazo no han sido del todo satisfactorios, por lo que ameritaría realizar procedimientos de restauración del cartílago, mediante técnicas de microfractura y trasplante autólogo. Conclusiones: las lesiones osteocondrales son trastornos frecuentes en deportistas, actualmente contamos con técnicas diagnósticas y terapéuticas como la artroscopia de rodilla, pero se debe considerar como estándar de oro la aplicación de otras técnicas como la microfractura y trasplante autólogo para renovación del cartílago y poder así impartir alivio sintomático mejorando la calidad de vida mediante la reparación de la superficie del cartílago articular.
4
Zhang, Jianyong, Zhendong Cui, Xiaopeng Chen, and Longfei Li. "Research Progress on the Microfracture of Shale: Experimental Methods, Microfracture Propagation, Simulations, and Perspectives." Applied Sciences 14, no. 2 (2024): 784. http://dx.doi.org/10.3390/app14020784.
Full textAbstract:
The fracture network generated by hydraulic fracturing in unconventional shale reservoirs contains numerous microfractures that are connected to macroscopic fractures. These microfractures serve as crucial pathways for shale gas to flow out from micro- and nano-scale pores, playing a critical role in enhancing shale gas recovery. Currently, more attention is being given by academia and industry to the evolution of macroscopic fracture networks, while the understanding of the microfracture mechanisms and evolution is relatively limited. A significant number of microfractures are generated during the hydraulic fracturing process of shale. These microfractures subsequently propagate, merge, and interconnect to form macroscopic fractures. Therefore, studying the fracture process of rock masses from a microscale perspective holds important theoretical significance and engineering value. Based on the authors’ research experience and literature review, this paper provides a brief overview of current progress in shale microfracture research from five aspects: in situ observation experiments of microfractures in shale, formation and evolution processes of discontinuous microfractures, the impact of inhomogeneity on microfracture propagation, measurement methods for microscale mechanical parameters and deformation quantities in shale, and numerical simulation of shale microfractures. This paper also summarizes the main challenges and future research prospects in shale microfracture studies, including: (1) quantitative characterization of in situ observation experimental data on shale microfractures; (2) formation and evolution laws of macroscopic, mesoscopic, and microscopic multi-scale discontinuous fractures; (3) more in-depth and microscale characterization of shale heterogeneity and its deformation and fracture mechanisms; (4) acquisition of shale micro-mechanical parameters; (5) refinement and accuracy improvement of the numerical simulation of microfractures in shale. Addressing these research questions will not only contribute to the further development of microfracture theory in rocks but also provide insights for hydraulic fracturing in shale gas extraction.
5
Li, Pingping, Qianshen Li, Lei Li, and Huayao Zou. "A New Method for Comprehensive and Quantitative Characterization of Shale Microfractures: A Case Study of the Lacustrine Shale in the Yuanba Area, Northern Sichuan Basin." Energies 16, no. 15 (2023): 5685. http://dx.doi.org/10.3390/en16155685.
Full textAbstract:
Microfractures can connect isolated pores within shale, significantly increasing the shale’s storage capacity and permeability, and benefiting shale gas exploitation. Therefore, the quantitative characteristics of microfractures are important parameters for shale reservoir evaluation. In this paper, taking the Jurassic Da’anzhai Member (J1z4) lacustrine shale in the Yuanba area of the northern Sichuan Basin as an example, we propose a method for comprehensive and quantitative characterization of shale microfractures that combines rock thin section (RTS) and scanning electron microscopy (SEM) observations. The different magnifications of RTSs and SEM images lead to the identification and characterization of microfractures of different scales using these two methods. RTSs are mainly used to characterize microfractures with widths larger than 10 μm, while SEM is mainly used to characterize microfractures with widths smaller than 10 μm. These techniques can be combined to comprehensively and quantitatively characterize microfractures of different scales in shale. The microfracture characterization results show that the average total porosity of the J1z4 shale is 4.46%, and the average microfracture surface porosity is 1.20% in the Yuanba area. The calculated average percentage of microfracture porosity to total porosity is 21.09%, indicating that the J1z4 shale reservoir space is dominated by pores and has the conditions for stable shale gas production and potential for shale gas exploration. However, the percentage of microfracture porosity to total porosity of shale near faults and fold zones approaches or exceeds 50%, which may lead to the loss of shale gas. The new method proposed in this study is also useful for quantitative characterization of shale microfractures in the Sichuan Basin and other basins.
6
Calvo R, Rafael, David Figueroa P, Nelson Morales C, Francisco Figueroa B, and Rafael Calvo M. "Lesión osteocondral extensa de cóndilo femoral; tratamiento en un tiempo con matriz colágena y concentrado de médula ósea – reporte de un caso." Revista Chilena de Ortopedia y Traumatología 58, no. 03 (2017): 100–105. http://dx.doi.org/10.1055/s-0037-1615254.
Full textAbstract:
ResumenEl tratamiento de las lesiones osteocondrales de gran tamaño y profundidad resultan un desafío debido a que las técnicas habituales (microfractura o transplante osteocondral autólogo), son insuficientes para cubrir el defecto; eso es particularmente importante en pacientes jóvenes, pues se debe intentar técnicas que generen la menor comorbilidad posible. Presentamos un caso de un paciente de 18 años con una lesión osteocondral de 6 cm2 por 14 mm de profundidad, tratado mediante autoinjerto óseo, concentrado de médula ósea y matriz colágena, con resultados satisfactorios tanto en lo funcional como en lo imagenológico. Esa técnica presenta la ventaja de realizarse en un tiempo y con una fuente de células troncales mesenquimáticas (Médula ósea), validada en la literatura y altamente reproducible.
7
Wang, Kai, Lianguo Wang, Bo Ren, and Hao Fan. "Study on Seepage Simulation of High Pressure Grouting in Microfractured Rock Mass." Geofluids 2021 (February 3, 2021): 1–12. http://dx.doi.org/10.1155/2021/6696882.
Full textAbstract:
In coal mines, under high in situ stress and strong mining activity, roadway surrounding rock commonly contains large amounts of larger fractures and microfractures. Along with the large deformation and continuous rheology of the soft rock roadway, the fractures in the surrounding rock are likely to be compressed and closed, forming undeveloped microfractures, which hinder conventional grouting support methods. Based on the fluid-solid coupling between slurry seepage and microfracture deformation, a theoretical model of microfracture grouting seepage is established. A program for the analysis and calculation of microfracture grouting is developed to quantitatively describe the variation in slurry seepage distance and fracture opening. Numerical experiments are carried out to study the grouting seepage of microfractures under different grouting pressures and fracture opening conditions, and the variation rules for the spatial distribution of fracture opening and slurry seepage distance during grouting pressure are obtained. Fluid-solid coupling has a significant influence on grout seepage characteristics. The grouting pressure and the fracture opening changes are nonlinearly attenuated along the grout seepage direction.
8
Kong, Xiangye, Jianhui Zeng, Xianfeng Tan, et al. "Genetic Types and Main Control Factors of Microfractures in Tight Oil Reservoirs of Jimsar Sag." Geofluids 2021 (July 23, 2021): 1–19. http://dx.doi.org/10.1155/2021/5558551.
Full textAbstract:
Microfractures are key for migrating and aggregating hydrocarbon source rocks and fracturing oil-gas exploitation in tight reservoirs. In this study, rock samples from the Lucaogou Formation tight reservoirs in Xinjiang, China, were studied using multidisciplinary techniques to investigate the genetic types and main control factors of microfractures. Results indicated that the Lucaogou Formation mainly developed diagenetic microfractures followed by tectonic microfractures, with slight formations of granular microfractures. These observations were used to clarify the relationship between the development of microfractures and the pore fluid content, lithology, mineral composition, and stratum thickness. A higher pore fluid content corresponded to a lower compressive strength of the rocks and a larger ring count, resulting in a higher probability of failure and microfracture formation. Tight reservoirs containing more quartz and carbonate minerals were found to develop more microfractures. Quartz grains showed fractures at the margins under stress, which increased the pore permeability of rocks. Carbonate minerals tended to form microfractures owing to corrosion. Microfracture formation mechanisms differed depending on lithology, and microfractures were found to develop most in dolomite and dolomitic siltstones and least in mudstone. Muddy rocks developed fewer tectonic fractures because they can easily absorb stress and undergo plastic deformation. Within a certain stratum thickness range, the average single-well fracture space and stratum thickness showed positive correlations. Moreover, the fracture space increased and the fracture density decreased as the stratum thickness increased. When the stratum thickness was less than 2.5 m, the fracture space increased linearly with the stratum thickness, and when the stratum thickness was greater than 2.5 m, the fracture space remained constant. This study will provide an essential scientific basis for enhancing tight oil recovery.
9
SHAYAN, MAHDIS, YOUNGJAE CHUN, WOOCHUL LIM, et al. "COMPUTATIONAL ANALYSIS OF THE REGENERATED KNEE STRUCTURE AFTER BONE MARROW STIMULATION TECHNIQUES." Journal of Mechanics in Medicine and Biology 15, no. 03 (2015): 1550036. http://dx.doi.org/10.1142/s0219519415500360.
Full textAbstract:
Bone marrow stimulation techniques, such as abrasion arthroplasty or microfracture, have been widely used for repairing cartilage; however, the mechanical stress analysis of these surgical techniques has not been fully investigated. In this study, finite element analysis was used to investigate stresses produced in complex structures (e.g., cartilage, subchondral bone and trabecular bone) using 2D knee structural models. Abrasion arthroplasty creates global damages only in subchondral bone, but, microfracture technique creates local damages in both trabecular and subchondral regions. Although stresses do not significantly change in trabecular bones as 50% recovery occurs in both abrasion and microfacture samples, significant changes are observed in both subchondral bone and cartilage layer depending on the procedure. The maximum stress levels in the microfractured bone represent approximately a 10.48% increase in cartilage and a 38.25% increase in subchondral bones compared to normal conditions. After 150% recovery, however, all three layers increase their stress levels in microfractured samples. Therefore, the 2D computational analysis results suggest that the microfracture technique should be cautiously used.
10
Sánchez-Santana, Ulises, Gerardo Presbítero-Espinosa, and José María Quiroga-Arias. "Application of Microfracture Analysis to Fatigue Fractures in Materials through Non-Destructive Tests." Materials 17, no. 4 (2024): 772. http://dx.doi.org/10.3390/ma17040772.
Full textAbstract:
Fatigue fractures in materials are the main cause of approximately 80% of all material failures, and it is believed that such failures can be predicted and mathematically calculated in a reliable manner. It is possible to establish prediction modalities in cases of fatigue fractures according to three fundamental variables in fatigue, such as volume, number of fracture cycles, as well as applied stress, with the integration of Weibull constants (length characteristic). In this investigation, mechanical fatigue tests were carried out on specimens smaller than 4 mm2, made of different industrial materials. Their subsequent analysis was performed through precision computed tomography, in search for microfractures. The measurement of these microfractures, along with their metrics and classifications, was recorded. A convolutional neural network trained with deep learning was used to achieve the detection of microfractures in image processing. The detection of microfractures in images with resolutions of 480 × 854 or 960 × 960 pixels is the primary objective of this network, and its accuracy is above 95%. Images that have microfractures and those without are classified using the network. Subsequently, by means of image processing, the microfracture is isolated. Finally, the images containing this feature are interpreted using image processing to obtain their area, perimeter, characteristic length, circularity, orientation, and microfracture-type metrics. All values are obtained in pixels and converted to metric units (μm) through a conversion factor based on image resolution. The growth of microfractures will be used to define trends in the development of fatigue fractures through the studies presented.
11
Ye, Zhenni, Enke Hou, Zhonghui Duan, and Zengjiang Li. "Coal Reservoir Characterization in a Tectonic Setting and the Effects of Tectonism on the Coalbed Methane (CBM) Content." Advances in Materials Science and Engineering 2019 (February 13, 2019): 1–11. http://dx.doi.org/10.1155/2019/7974628.
Full textAbstract:
Research on the relationships among tectonics, micropores, microfractures, and coalbed methane (CBM) content is important for the optimal selection of CBM production areas. In this study, micropore-microfracture structural parameters of coal samples from the Guojiahe coalfield are determined through the use of X-ray photography, an image recognition algorithm, and a liquid nitrogen adsorption method. The relationship between the micropore-microfracture characteristics of the reservoir and the gas content is quantitatively assessed using the Grassberger and Procaccia (GP) algorithm to calculate the correlation dimension of the parameters. Micropore-microfracture development varies in different tectonic zones. Additionally, the CBM content varies according to the characteristic parameters of hysteresis loops and the pore diameter. The correlation dimension is an effective indicator of the nonlinear relationship between reservoir micropore-microfracture characteristics and the gas content.
12
Taleghani, A. Dahi, M. Ahmadi, W. Wang, and Jon E. Olson. "Thermal Reactivation of Microfractures and Its Potential Impact on Hydraulic-Fracture Efficiency." SPE Journal 19, no. 05 (2014): 761–70. http://dx.doi.org/10.2118/163872-pa.
Full textAbstract:
Summary Core studies have revealed the presence of abundant cemented microfractures in many tight formations. Further independent studies have revealed the opening of some of these microfractures on the wall surface of main hydraulic fractures. In addition, early-production well-testing analysis in some of these cases provides estimates for the hydraulically-induced-fracture surface area, which is much larger than fracture dimensions estimated in fracturing design or provided by the location of microseismic events. Opening of small-sized fractures could be a possible reason for this discrepancy. In this paper, we show to what extent thermal stresses induced by temperature difference between fracturing fluid and formation fluid could provide the driving force to open a portion of these small, cemented natural fractures lying on the surface of hydraulic fractures. Moreover, through combination of stress analysis and empirical fracture-distribution models obtained from outcrops, we calculate the increase of total reservoir/fracture contact surface under the condition of microfracture activation. Our thermoelasticity analysis reveals the effect of the pump rate and temperature of the fracturing fluid on the number of activated microfractures. The results show that the volume of the microfractures varies depending on the length of the microfracture, rock properties, and time. At the end of the paper, through an example, we show that activation of only a small portion of these microfractures can increase the total fracture/formation contact area considerably and, consequently, increase initial production. Reservoir-pressure changes caused by production might partially close or reopen these microcracks during production; hence, the effectiveness of these microfractures could be mainly restricted to the early life of the reservoirs.
13
Kiuru, Risto, Dorka Király, Gergely Dabi, and Lars Jacobsson. "Comparison of DFN Modelled Microfracture Systems with Petrophysical Data in Excavation Damaged Zone." Applied Sciences 11, no. 7 (2021): 2899. http://dx.doi.org/10.3390/app11072899.
Full textAbstract:
Physical and petrographic properties of drill core specimens were determined as a part of investigations into excavation damage in the dedicated study area in the ONKALO® research facility in Olkiluoto, Western Finland. Microfractures in 16 specimens from two drillholes were analysed and used as a basis for fractal geometry-based discrete fracture network (DFN) modelling. It was concluded that the difference in resistivity between pegmatoid granite (PGR) and veined gneiss (VGN) specimens of similar porosity was likely due to differences in the types of microfractures. This hypothesis was confirmed from microfracture analysis and simulation: fractures in gneiss were short and mostly in one preferred orientation, whereas the fractures in granite were longer and had two preferred orientations. This may be due to microstructure differences of the rock types or could suggests that gneiss and granite may suffer different types of excavation damage. No dependencies on depth from the excavated surface were observed in the geometric parameters of the microfractures. This suggests that the excavation damaged zone cannot be identified based on the changes in the parameters of the microfracture networks, and that the disturbed layer observed by geophysical methods may be caused by macro-scale fractures.
14
Steadman, J. Richard, William G. Rodkey, and Karen K. Briggs. "Microfracture." CARTILAGE 1, no. 2 (2010): 78–86. http://dx.doi.org/10.1177/1947603510365533.
Full textAbstract:
Development and implementation of the microfracture technique began in the early 1980s. The surgical goal was to produce “microfractures” in the subchondral bone perpendicular to the surface and to be able to reach all areas of the joint with the instruments. The microfracture technique has been demonstrated to be an effective arthroscopic treatment for full-thickness chondral lesions and joints with degenerative lesions. This technique is cost effective, technically not complicated, has an extremely low rate of associated patient morbidity, and leaves options for further treatment. Patient compliance with rehabilitation, knee alignment, and the depth of the cartilage rim surrounding the lesion are a few of the factors that can affect the outcomes following microfracture.
15
Pang, Mengqiang, Jing Ba, Li-Yun Fu, José M. Carcione, Uti I. Markus, and Lin Zhang. "Estimation of microfracture porosity in deep carbonate reservoirs based on 3D rock-physics templates." Interpretation 8, no. 4 (2020): SP43—SP52. http://dx.doi.org/10.1190/int-2019-0258.1.
Full textAbstract:
Carbonate reservoirs in the S area of the Tarim Basin (China) are ultradeep hydrocarbon resources, with low porosity, complex fracture systems, and dissolved pores. Microfracturing is a key factor of reservoir connectivity and storage space. We have performed measurements on limestone samples, under different confining pressures, and we used the self-consistent approximation model and the Biot-Rayleigh theory of double porosity to study the microfractures. We have computed the fluid properties (mainly oil) as a function of temperature and pressure. Using the dependence of seismic [Formula: see text] on the microfractures, a multiscale 3D rock-physics template (RPT) is built, based on the attenuation, P-wave impedance, and phase velocity ratio. We estimate the ultrasonic and seismic attenuation with the spectral-ratio method and the improved frequency-shift method, respectively. Then, calibration of the RPTs is performed at ultrasonic and seismic frequencies. We use the RPTs to estimate the total and microfracture porosities. The results indicate that the total porosity is low and the microfracture porosity is relatively high, which is consistent with the well log data and actual oil production reports. This work presents a method for identification of deep carbonate reservoirs by using the microfracture porosity estimated from the 3D RPT, which could be exploited in oil and gas exploration.
16
Guo, Zhiqi, Xiaoying Qin, and Cai Liu. "Pore and Microfracture Characterization in Tight Gas Sandstone Reservoirs with a New Rock-Physics-Based Seismic Attribute." Remote Sensing 15, no. 2 (2023): 289. http://dx.doi.org/10.3390/rs15020289.
Full textAbstract:
Pores and microfractures provide storage spaces and migration pathways for gas accumulation in tight sandstones with low porosity and permeability, acting as one of the controlling factors of gas production. The development of a rational rock physics model is essential for better understanding the elastic responses of tight sandstone with complex pore structures. Accordingly, seismic characterization of pores and microfractures based on the rock physics model provides valuable information in predicting high-quality tight gas sandstone reservoirs. This paper proposes a rock-physics-based approach to compute the pore–microfracture indicator (PMI) from elastic properties for pore structure evaluation in tight sandstones. The PMI is achieved based on the axis rotation of the elastic parameter space using well-log data. The rotation angle is determined by finding the maximum correlation between the linearized combination of the elastic parameters and the introduced factor associated with total porosity and microfracture porosity. The microfracture porosity is then estimated with an inversion scheme based on the double-porosity model. Finally, the optimized rotation angle is employed to compute the PMI with seismic data. The obtained results are of great benefit in predicting the permeable zones, providing valuable information for sweet spot characterization in tight gas sandstone reservoirs.
17
Liu, Zhi Hua, Jun Gang Liu, Yi Guo Dong, Yang Chen, Li Ren Xing, and Zhi Qiang Liu. "Microstructure of Mid and High Rank Coals from Qinshui Basin, North China and its Contribution to Coalbed Meathane." Advanced Materials Research 616-618 (December 2012): 201–7. http://dx.doi.org/10.4028/www.scientific.net/amr.616-618.201.
Full textAbstract:
To better understand the relationship between micro-structures and coalbed methane(CBM), characterisation methods including microscopic photometer, scanning electron microscopy (SEM), mercury porosimetry, nitrogen adsorption at 77K and methane isothermal adsorption were introduced into investigating the adsorption capability of coal reservoir. The results reveal that the micropores volume has a increasing trend with increased vitrinite reflectance. The most favorable pore type is to have good connectivity, very good micro-pores porosity and good adsorption capability. Statistical analysis shows that endo-microfractures are the main type microfractures of Qinshui basin. Based on the results of coal macerals, coal lithotypes, it is found that the bright coal and telocollinites are favorable for endo-fractures formation. Obviously different from the formation of endo-microfracture, exo-microfracture strongly relates to the coal structure. A good match between the fractures and the pores is needed for a favorable CBM reservoir. Based on the evaluation of pore-fracture system, Yangquan is the second CBM commercial area of Qinshui basin.
18
Jordi, Navinés-López, Pardo Aranda Fernando, Cremades Pérez Manel, et al. "O-017 - MICROFRACTURA-COAGULACIÓN PARA LA TRANSECCIÓN ROBÓTICA REAL DEL PARÉNQUIMA HEPÁTICO. DESCRIPCIÓN DE LA TÉCNICA E INDICACIONES." Cirugía Española 102 (November 2024): 376–77. https://doi.org/10.1016/s0009-739x(25)00420-8.
Full text
19
Wang, Hu, Zhiliang He, Yonggui Zhang, Kun Su, and Ruyue Wang. "Quantitative identification of microfractures in the marine shale reservoir of the Wufeng-Longmaxi Formation using water immersion tests and image characterization." Interpretation 6, no. 4 (2018): SN23—SN30. http://dx.doi.org/10.1190/int-2018-0010.1.
Full textAbstract:
Identification of natural microfractures is important for shale reservoir evaluation. In total, 42 selected core samples from the Wufeng-Longmaxi marine shales in the Fuling gas field, southeastern Sichuan Basin, were analyzed using water-immersion testing, computed tomography scanning, and argon-ion polishing scanning electron microscope experiments, along with edge detection and image stitching analysis methods. The results indicate that the immersion experiment is an effective way to identify natural fractures. Three types of natural microfractures correspond to bubble positions with 250 nm resolution scanning electron microscopy: bedding fractures, particle edge fractures, and dissolution fractures. The bedding and dissolution fractures show the same occurrence as the strata, and they are the main bubbling channels. The occurrence of particle edge fractures varies significantly. Microfractures are capable of forming a fracture network, connecting separated storage spaces in the shale reservoir. The best fracture network is formed by bedding and dissolution fractures in 3D space. Furthermore, apportion of the particle edge and dissolution fractures is capable of forming microfracture networks in shale cores increasing the connectivity of pore spaces. The number of bubble points also indicates a positive correlation with shale laminae, which indicates that microfractures are developed mainly within the laminae. The number of shale laminae and the number of microfracture channels can be calculated quantitatively by the number of bubble points. The observations can be used in the drilling site to estimate the physical properties of shale reservoirs quickly and quantitatively.
20
Zhang, Hai Yong, Shun Li He, Guo Hua Luan, Shao Yuan Mo, Zhi Kai Lv, and Gang Lei. "Experimental Study on Stress Sensitivity of Ultra-Low Permeability Sandstones." Applied Mechanics and Materials 318 (May 2013): 279–83. http://dx.doi.org/10.4028/www.scientific.net/amm.318.279.
Full textAbstract:
Ultra-low permeability rocks have plenty of microfractures. The stress-dependent permeability has a significant impact on the seepage. Previous studies are mainly on the permeability variation with stress in low permeability reservoir. But few are involved in ultralow permeability cores. In this paper, the experiment of stress sensitive ultralow permeability cores which are fabricated (both matrix cores and microfracture cores) is conducted. The experimental results shows that the permeability of microfracture low permeability cores which are fabricated increases greatly while the porosity of low permeability cores is little affected. This indicates that the fabricated microfracture cores are in line with that of the real situations of fracture media reservoir. By comparison, the permeability stress sensitive hysteresis degree of microfracture cores is not apparent and the permeability recovery degree is high in the unloading cycle. This study is of great benefit to reveals the stress sensitivity features of ultralow permeability reservoir
21
Loppini, Mattia, Francesco La Camera, Francesco Manlio Gambaro, Riccardo Ruggeri, Guido Grappiolo, and Federico Della Rocca. "Sport Activity and Clinical Outcomes after Hip Arthroscopy with Acetabular Microfractures at a Minimum 2-Year Follow-Up: A Matched-Pair Controlled Study." Life 12, no. 8 (2022): 1107. http://dx.doi.org/10.3390/life12081107.
Full textAbstract:
Background: Acetabular microfractures for cartilage lesions have been shown to be a safe procedure able to improve patient reported outcomes (PROs). Nevertheless, the return to sport activity rate represents a crucial outcome to be investigated in these young athletic patients. Methods: Patients undergoing acetabular microfracture for full chondral acetabular lesions were compared to a 1:1 matched-pair by age and gender control group undergoing hip arthroscopy without microfractures. Clinical assessment was performed with PROs and participation in sports in terms of type and level of activities was evaluated preoperatively and at 2-years follow-up. Results: A total of 62 patients with an average age of 35.1 ± 8.1 (microfracture group) and 36.4 ± 6.3 (control group) were included. In both groups, the average values of PROs significantly increased from preoperatively to the last follow-up. There was no significant difference between the two groups in the number of patients playing at the amateur and elite level preoperatively and at the last follow-up. Conclusions: Microfractures for the management of full-thickness acetabular chondral defect provides good clinical results at a minimum follow-up of two years, which are not inferior to a matched-pair control group. Patients undergoing this procedure are likely able to return at the same level of sport before surgery.
22
Liang, Feng, Yanhui Han, Hui-Hai Liu, Rajesh Saini, and Jose I. Rueda. "An Improved Hydraulic Fracturing Treatment for Stimulating Tight Organic-Rich Carbonate Reservoirs." SPE Journal 25, no. 02 (2020): 632–45. http://dx.doi.org/10.2118/199880-pa.
Full textAbstract:
Summary Hydraulic fracturing has been widely used in stimulating tight carbonate reservoirs to improve oil and gas production. Improving and maintaining the connectivity between the natural and induced microfractures in the far-field and the primary fracture networks are essential to enhancing the well production rate because these natural and induced unpropped microfractures tend to close after the release of hydraulic pressure during production. This paper provides a conceptual approach for an improved hydraulic fracturing treatment to enhance the well productivity by minimizing the closure of the microfractures in tight carbonate reservoirs and enlarging the fracture aperture. The proposed improved fracturing treatment was to use the mixture of the delayed acid-generating materials along with microproppants in the pad/prepad fluids during the engineering process. The microproppants were used to support the opening of natural or newly induced microfractures. The delayed acid-generating materials were used in this strategy to enlarge the flow pathways within microfractures owing to degradation introduced under elevated temperatures and interaction with the calcite formation. The feasibility of the proposed approach is evaluated by a series of the proof-of-concept laboratory coreflood experiments and numerical modeling results. First, one series of experiments (Experiments 1–3) was designed to investigate the depth of the voids on the fracture surface generated by the solid delayed acid-generating materials under different flow rates of the treatment fluids and different temperatures. This set of tests was conducted on a core plug assembly that was composed of half-core Eagle Ford Sample, half-core hastelloy core plug, and a mixture of solid delayed acid-generating materials [polyglycolic acid (PGA)] along with small-sized proppants sandwiched by two half-cores. Surface profilometer was used to quantify the surface-etched profile before and after coreflood experiments. Test results have shown that PGA materials were able to create voids or dimples on the fracture faces by their degradation under elevated temperature and the chemical reaction between the generated weak acid and the calcite-rich formation. The depth of the voids generated is related to the treatment temperature and the flow rate of the treatment fluids. Experiment 4 was conducted using two half-core splits to quantify the improvement factor of the core permeability due to the treatment with mixed sand and PGA materials. Simulations of fluid flow through proppant assembly (inside of the microfractures) using the discrete element method (DEM)–lattice Boltzmann method (LBM) coupling approach for three different scenarios (14 cases in total) were further conducted to evaluate the fracture permeability and conductivity changes under different situations such as various gaps between proppant particulates and different depths of voids generated on fracture faces: (1) fluid flow in a microfracture without proppant, (2) fluid flow in a microfracture with small-sized proppants, and (3) fluid flow in a microfracture supported by small-sized proppants and generated voids on the fracture walls. The simulation results show that with proppant support (Scenario 2), the microfracture permeability can be increased by tens to hundreds of times in comparison to Scenario 1, depending on the gaps between proppant particles. The permeability of proppant-supported microfracture (Scenario 3) can be further enhanced by the cavities created by the reactions between the generated acid and calcite formation. This work provides experimental evidence that using the mixture of the solid delayed acid-generating materials along with microproppants or small-sized proppants in stimulating tight carbonate reservoirs in the pad/prepad fluids during the engineering process may be able to effectively improve and sustain permeability of flow pathways from microfractures (either natural or induced). These findings will be beneficial to the development of an improved hydraulic fracturing treatment for stimulating tight organic-rich carbonate reservoirs.
23
Manunta, Andrea, and Anna Manconi. "The treatment of chondral lesions of the knee with the microfracture technique and platelet-rich plasma." Joints 01, no. 04 (2013): 167–70. http://dx.doi.org/10.11138/jts/2013.1.4.167.
Full textAbstract:
Purpose: to assess the efficacy of associating the microfracture technique with platelet-rich plasma (PRP) injections in the treatment of chondral lesions to promote acceleration and optimization of the healing process compared with the traditional microfracture approach. Methods: from September 2011 to August 2012, 20 patients (9 males and 11 females, aged 30-55 years) were treated. All presented with chondral lesions of the medial femoral condyle of the knee and a pain duration ranging from 8 to 12 months.The patients were randomized into two groups (A and B). Group A was treated with the microfracture technique and a total of three intra-articular injections of PRP. Group B was treated with microfractures alone. Clinical follow-up was performed at 3, 6 and 12 months after treatment. Clinical function was assessed on the basis of the International Knee Documentation Committee (IKDC) score. Pain was evaluated using a visual analogue scale (VAS) Results: the patients in group A had a mean baseline IKDC score of 31.2, which rose to 84.2 at 12 months. The IKDC scores in group B were at 30.1 at baseline and 81 at 12 months. Conclusions: the results of our study suggest that functional recovery and resolution of pain are obtained more quickly in PRP-treated patients. We also observed a better functional outcome in the patients treated with the combination of PRP and microfractures, even at 12 months, although the difference was not statistically significant. Level of evidence: level II, randomized clinical study.
24
McIlwraith, C. Wayne, and David D. Frisbie. "Microfracture." CARTILAGE 1, no. 2 (2010): 87–95. http://dx.doi.org/10.1177/1947603510367427.
Full textAbstract:
The therapeutic value of microfracture has been demonstrated in clinical patients. The rationale is that focal penetration of the dense subchondral plate exposes cartilage defects to the benefits of cellular and growth factor influx in addition to improving anchorage of the new tissue to the underlying subchondral bone and, to some extent, the surrounding cartilage. While functional outcomes have been reported, there is a paucity of data on the histological, biochemical, and molecular changes in human patients. This paper reviews 4 basic science studies of microfracture using an equine chondral defect model that gave some insight into possible mechanisms of action and also how the microfracture response could be augmented. In study I, microfracture of full-thickness chondral defects in exercised horses significantly increased the repair tissue volume in the defects at both 4 and 12 months. No adverse effects were seen. In study II, an investigation of the healing of full-thickness chondral defects during the first 8 weeks with or without microfracture demonstrated that microfracture significantly increased type II collagen expression as early as 8 weeks after treatment compared to controls; aggrecan expression was progressively increased during the first 8 weeks but was not significantly enhanced by microfracture. In study III, it was demonstrated that removal of the calcified cartilage layer provided optimal amount and attachment of repair tissue, emphasizing that careful removal of calcified layer is critical during debridement prior to microfracture. Study IV assessed the ability of IL-1ra/IGF-1 combination gene therapy to further modulate repair of microfractured chondral defects. The repair tissue in gene therapy–treated joints demonstrated increased proteoglycan and type II collagen content compared to microfracture alone.
25
Sun, Yucheng, Jae-Man Kwak, Erica Kholinne, et al. "Small Subchondral Drill Holes Improve Marrow Stimulation of Rotator Cuff Repair in a Rabbit Model of Chronic Rotator Cuff Tear." American Journal of Sports Medicine 48, no. 3 (2020): 706–14. http://dx.doi.org/10.1177/0363546519896350.
Full textAbstract:
Background: Microfracture of the greater tuberosity has been proved effective for enhancing tendon-to-bone healing after rotator cuff repair. However, no standard diameter for the microfracture has been established. Purpose/Hypothesis: This study aimed to assess treatment with large- and small-diameter microfractures to enhance healing during rotator cuff repair surgery in a rabbit model of chronic rotator cuff tear. It was hypothesized that a small-diameter microfracture had advantages in terms of tendon-to-bone integration, bone-tendon interface maturity, microfracture healing, and biomechanical properties compared with a large-diameter microfracture. Study Design: Controlled laboratory study. Methods: Bilateral supraspinatus tenotomy from the greater tuberosity was performed on 21 New Zealand White rabbits. Bilateral supraspinatus repair was performed 6 weeks later. Small-diameter (0.5 mm) microfracture and large-diameter microfracture (1 mm) were performed on the left side and right side, respectively, in 14 rabbits as a study group, and simple repair without microfracture was performed in 7 rabbits as a control group. At 12 weeks later, 7 of 14 rabbits in the study group were sacrificed for micro–computed tomography evaluation and biomechanical testing. Another 6 rabbits were sacrificed for histological evaluation. In the control group, 3 of the 7 rabbits were sacrificed for histological evaluation and the remaining rabbits were sacrificed for biomechanical testing. Results: Significantly better bone-to-tendon integration was observed in the small-diameter microfracture group. Better histological formation and maturity of the bone-tendon interface corresponding to better biomechanical results (maximum load to failure and stiffness) were obtained on the small-diameter microfracture side compared with the large-diameter side and the control group. The large-diameter microfracture showed worse radiographic and histological properties for healing of the microfracture holes on the greater tuberosity. Additionally, the large-diameter microfracture showed inferior biomechanical properties but similar histological results compared with the control group. Conclusion: Small-diameter microfracture showed advantages with enhanced rotator cuff healing for biomechanical, histological, and radiographic outcomes compared with large-diameter microfracture, and large-diameter microfracture may worsen the rotator cuff healing. Clinical Relevance: This animal study suggested that a smaller diameter microfracture may be a better choice to enhance healing in clinical rotator cuff repair surgery in humans.
26
Tan, Shijie Ian, Samuel Jun Wei Tho, and Kam San Tho. "Biological resurfacing of grade IV articular cartilage ulcers in knee joint with Hyalofast." Journal of Orthopaedic Surgery 28, no. 1 (2020): 230949902090515. http://dx.doi.org/10.1177/2309499020905158.
Full textAbstract:
Introduction: Hyalofast grafting with microfracture is a new minimally invasive treatment method being proposed for joint cartilage defects. This study was done to measure the clinical efficacy of Hyalofast grafting after microfractures. Methods: Forty-six patients were assessed for knee function using knee injury and osteoarthritis outcome score (KOOS) after undergoing microfracture and Hyalofast grafting surgery. We further divided the 46 patients into a group of 10 patients who had no associated procedures done with the microfracture and Hyalofast grafting surgery. All patients had magnetic resonance imaging (MRI) of the affected knee pre-surgery and two patients had MRI done post-surgery. Due to another unrelated injury, we were also able to obtain further arthroscopic findings of another patient’s knee 18 months after microfracture and Hyalofast grafting. Results: There was a statistically significant improvement in all categories of the KOOS (symptoms, pain, daily living, sports and quality of life) compared between years 1, 2 and 3 against pre-surgery. For the subgroup of Hyalofast only, there was a statistically significant improvement in symptoms, pain and daily living categories of the KOOS compared between years 1, 2 and 3 against pre-surgery. Conclusions: Our study shows that Hyalofast grafting after microfracture is a viable alternative to treatment for patients with grade 4 cartilage ulcers.
27
Abbakumov, K. E., A. V. Vagin, and I. G. Sidorenko. "Acoustical characteristics of solid elastic mediums with oriented microfructures." Дефектоскопия, no. 4 (April 15, 2023): 3–13. http://dx.doi.org/10.31857/s0130308223040012.
Full textAbstract:
Model for interaction of plane elastic longitudinal waves with contains oriented microfractures with specific boundary conditions for “linear slip@ approximation is developed. The form of dispersion equation is defined in approximation of Bloch and Floque waves theory. Results of its solution which define character of functions for propagation phase velocity and attenuation coefficient of effective longitudinal wave in dependence on crack faces microfracture parameters and other model parameters.
28
Chen, Yushu, Qihua Zhao, Jindong Xiang, and Yi Peng. "Complex Network Modeling and Analysis of Microfracture Activity in Rock Mechanics." Applied Sciences 15, no. 10 (2025): 5242. https://doi.org/10.3390/app15105242.
Full textAbstract:
This study employs rock triaxial acoustic emission laboratory tests to investigate the activity of microfractures in plagiogranite from the Yebatan hydropower station dam area. By integrating interdisciplinary theories—including spatiotemporal single-link groups, fractal theory, complex networks, and graph theory—we develop a complex network model of rock microfractures. Results demonstrate that the microfracture network, characterized by the average degree (<k>) and clustering coefficient (<c>), undergoes distinct evolutionary stages during rock deformation and failure. The complex network parameters <k> and <c> undergo abrupt increases and decreases. These changes serve as characteristic indicators of the transition from stable to unstable states in rock deformation and failure, providing new insights into predicting rock failure and instability.
29
Zhang, Hai Yong, Shun Li He, Guo Hua Luan, Shao Yuan Mo, Zhi Kai Lv, and Gang Lei. "Study on Stress Sensitivity in Microfracture Ultra-Low Permeability Reservoir." Advanced Materials Research 772 (September 2013): 802–7. http://dx.doi.org/10.4028/www.scientific.net/amr.772.802.
Full textAbstract:
The stress-dependent permeability of ultra-low permeability rocks has a significant impact on the seepage. A number of experimental studies on the variation of permeability with stress change in low permeability reservoir have been done, but few are involved in ultra-low permeability cores. In this study, first, we fabricated the shear-stress microfracture cores and then the stress sensitive experiments were conducted. Second, a fracture deformation model was introduced in order to depict the stress sensitivity features of fracture media theoretically. Finally, a comparison of the theoretical curves with the experimental data had been done. The results show that the fabricated microfracture cores can be used in the permeability stress sensitive experiments. The permeability stress sensitive hysteresis of the microfracture cores is not obvious and the recovery degree of stress sensitive hysteresis is high in the unloading cycle for the grains were compacted in the process of shearing. The theoretical curves have the desired behavior which is consistent with the experimental data well. It indicates that the method of fabricating microfractures can similarly reveal the stress sensitivity features of the real microfracture ultralow permeability reservoir. This study do great benefit to reveal the stress sensitivity features of ultra-low permeability reservoir.
30
Gao, Meiben, Tianbin Li, Junxun Zhu, Hongyu Yin, and Yongyi Yang. "An Analysis of Relationship between the Microfracture Features and Mineral Morphology of Granite." Advances in Civil Engineering 2021 (July 30, 2021): 1–6. http://dx.doi.org/10.1155/2021/4765731.
Full textAbstract:
Using the techniques of X-ray diffraction, polarizing microscopy, uniaxial compression, and scanning electron microscopy (SEM), the relationships between the microfracture features and mineral morphology of granite were studied. The results showed that feldspar, quartz, and biotite are the main components of the granite samples in this study. Biotite has a self-shaped flake structure with perfect cleavage. K-feldspar has a lattice double crystal structure with two groups of cleavage. Plagioclase has a semi-self-shaped plate structure with two groups of cleavage. Quartz is prismatic or granular and exhibits noncleavage. The microfracture features of biotite are flaky with exfoliation, and flake cleavage fracture is mainly determined by its peculiar flaky cleavage. Feldspar (K-feldspar and plagioclase) is plate, layered, or two groups of cleavage and is also mainly determined by its peculiar two groups of cleavage. The microfracture features of quartz are highly irregular, with many randomly distributed intergranular and transgranular cracks, small particles or granule bulges, similar to quartz crystal, and this is due to the noncleavage feature of quartz itself. It is demonstrated that microfractures are preferentially ruptured along cleavage planes for these granite minerals under the action of external forces.
31
Nian, Tao, Yanze Li, Tao Hou, Chengqian Tan, and Chao Liu. "Natural fractures at depth in the Lower Cretaceous Kuqa Depression tight sandstones: identification and characteristics." Geological Magazine 157, no. 8 (2020): 1299–315. http://dx.doi.org/10.1017/s0016756819001444.
Full textAbstract:
AbstractThe Kuqa Depression in the northern Tarim Basin, NW China, is characterized by fault-controlled anticlines where natural fractures may influence production. Natural fractures in the Lower Cretaceous tight sandstones in the depression have been studied using seismic profiles, borehole images, cores and thin-sections. Results show that thrust faults, two types of opening-mode macrofractures and two types of microfractures are present. Thrust faults were generated during Cenozoic N–S-directed tectonic shortening and have hydraulically linked Jurassic source rocks and Cretaceous sandstones. Opening-mode fractures can be subdivided on the basis of sizes, filling characteristics and distribution patterns. Type 1 macrofractures are barren or mainly calcite-lined. They have straight traces with widths (opening displacements) that are of the order of magnitude of 10 μm, suggesting that their primary role is that of migration channels. Type 2 macrofractures are calcite-filled opening-mode fractures. They have an elliptical or tabular shape with sharply tapering tips. Transgranular microfractures are lens-shaped and open or filled mostly by calcite; maximum widths range between 0.01 mm and 0.1 mm. Intragranular microfractures are the most common microfracture type. They are filled by calcite, feldspar or quartz. The macrofractures and transgranular microfractures have regular distributions, while most intragranular microfractures are irregularly distributed owing to their inherited origin. The results imply that natural fractures in the tight sandstones were formed as tectonic, diagenetic and natural hydraulic origins. In situ stress and cementation analyses suggest that Type 1 macrofractures and their genesis-related microfractures have controlled the present flow system of the tight sandstones.
32
Renard, François, Jessica McBeck, Neelima Kandula, Benoît Cordonnier, Paul Meakin, and Yehuda Ben-Zion. "Volumetric and shear processes in crystalline rock approaching faulting." Proceedings of the National Academy of Sciences 116, no. 33 (2019): 16234–39. http://dx.doi.org/10.1073/pnas.1902994116.
Full textAbstract:
Understanding the approach to faulting in continental rocks is critical for identifying processes leading to fracturing in geomaterials and the preparation process of large earthquakes. In situ dynamic X-ray imaging and digital volume correlation analysis of a crystalline rock core, under a constant confining pressure of 25 MPa, are used to elucidate the initiation, growth, and coalescence of microfractures leading to macroscopic failure as the axial compressive stress is increased. Following an initial elastic deformation, microfractures develop in the solid, and with increasing differential stress, the damage pervades the rock volume. The creation of new microfractures is accompanied by propagation, opening, and closing of existing microfractures, leading to the emergence of damage indices that increase as powers of the differential stress when approaching failure. A strong spatial correlation is observed between microscale zones with large positive and negative volumetric strains, microscale zones with shears of opposite senses, and microscale zones with high volumetric and shear strains. These correlations are attributed to microfracture interactions mediated by the heterogeneous stress field. The rock fails macroscopically as the microfractures coalesce and form a geometrically complex 3D volume that spans the rock sample. At the onset of failure, more than 70% of the damage volume is connected in a large fracture cluster that evolves into a fault zone. In the context of crustal faulting dynamics, these results suggest that evolving rock damage around existing locked or future main faults influences the localization process that culminates in large brittle rupture events.
33
Bilsel, İsmail Kerem, Fatih Yıldız, Mehmet Kapıcıoglu, et al. "Efficacy of Bone Marrow-Stimulating Technique in Rotator Cuff Repair." Orthopaedic Journal of Sports Medicine 5, no. 2_suppl2 (2017): 2325967117S0008. http://dx.doi.org/10.1177/2325967117s00080.
Full textAbstract:
Background: This study investigates the effect of microfracture as a bone marrow-stimulating(BMS) technique on rotatory cuff(RC) healing using a chronic RC tear model. Methods: Chronic retracted RC tendon tear model was created in the subscapularis(SSC) tendons of 20 New Zealand rabbits, bilaterally. The tendons were repaired after eight weeks using a single-row configuration with suture anchors. In right shoulders, tendons were repaired in a standard fashion(control group). In left shoulders, microfractures were performed on the SSC footprint before repair(microfracture group). The animals were sacrificed 8 and 16 weeks after repair. The repaired tendons were tested biomechanically for their ultimate failure load, linear stiffness and elongation at failure. Gross and histological evaluation of the tendon-to-bone healing was evaluated. Results: In every sample, the SSC tendon was attached to its footprint on the lesser tuberosity. In microfracture group, collagen fibers were organized in relatively ticker bundles at both time intervals. The mean ultimate failure load of microfracture was significantly greater than that of control group at 8 (148.4+31 N vs. 101.4+26 N; p=0.011) and 16 (155+30 N vs. 114.9+25 N; p=0.017) weeks after repair, respectively. There were no significant differences between the two groups at each time interval for linear stiffness (15.9+2.7N/mm vs. 15.8+1.3N/mm, p=0.798 and 16.9+4.3N/mm vs. 17.1+3.6N/mm, p=0.848, respectively) and elongation at failure (4.7+1.1 mm vs. 4.7+1.3 mm, p=0.848 and 4.8+1.5 mm vs. 4.9+0.9 mm, p=0.749, respectively). Conclusions: The BMS technique of microfracture on the tuberosity of the repaired chronic rotator cuff tear promotes the dynamic tendon healing with significant ultimate force to failure and apparent microscopic findings.
34
Chi, Lu, and Zoya Heidari. "Diffusional coupling between microfractures and pore structure and its impact on nuclear magnetic resonance measurements in multiple-porosity systems." GEOPHYSICS 80, no. 1 (2015): D31—D42. http://dx.doi.org/10.1190/geo2013-0467.1.
Full textAbstract:
Nuclear magnetic resonance (NMR) relaxation time measurements, although among the most accurate methods to estimate formation porosity, have been considered conventionally as insensitive to the presence of microfractures. Hence, the NMR responses in multiple-porosity systems, which may contain intergranular pores, microfractures, or channel-like inclusions, have not yet been thoroughly investigated. NMR pore-scale simulations using a random-walk algorithm enabled us to quantify the impact of microfractures/channels on NMR measurements and to propose a new concept of fracture-pore diffusional coupling in such heterogeneous systems. We randomly distributed and oriented microfractures (or channels) in 3D pore-scale images of different rock matrices. We then quantified the sensitivity of NMR [Formula: see text] (spin-spin relaxation time) distribution to the presence of microfractures (or channels) and compared the pore-scale simulation results against a previously published experimental study. The pore-scale simulation results from synthetic rock samples revealed that NMR [Formula: see text] distribution can be influenced not only by the pore-size distribution but also significantly by fracture-pore diffusional coupling. The intergranular pore size can be underestimated by up to 29%, and the volume fraction of intergranular pores can be underestimated by more than 10%, if the impact of diffusional coupling was not taken into account in interpretation of NMR measurements. Furthermore, we developed a simplified 1D analytical model for fracture-pore diffusional coupling. The analytical solutions of the 1D model were in agreement with the simulation results in the synthetic rock samples, which further demonstrated the existence of fracture-pore coupling in multiple-porosity systems. The developed 1D model enabled real-time evaluation of diffusional coupling effect in the presence of microfractures and complex pore-size distribution. The results were promising for future applications of NMR relaxometry for the assessment of microfracture content, when combined with other conventional well logs.
35
Bardas, Ciprian Alin, Gabri Jozsef Zsolt, Dragos Apostu, Daniel Oltean Dan, Gheorghe Tomoaia, and Horea Rares Ciprian Benea. "Functional Results of Different Repair Techniques for Knee Articular Cartilage Lesions." Revista de Chimie 69, no. 11 (2018): 3288–91. http://dx.doi.org/10.37358/rc.18.11.6732.
Full textAbstract:
The articular cartilage lesions are frequent and highly affect the patient�s quality of life. Although remarkable progress in the treatment of focal lesions of articular cartilage were lately made, controversies still exist regarding the treatment options. The main purpose of this study was to evaluate and compare the preoperative and 6 months postoperative knee functional scores of patients undergoing arthroscopic repair of knee chondral lesions by: debridement, microfractures, osteochondral autograft transplantation and autologous matrix-induced chondrogenesis. Chondral reconstruction with collagen membranes and osteochondral autograft transplantation techniques showed a superior result at 6 months postoperatively compared to microfracture techniques and mechanical debridement.
36
Aita, Marcio Aurelio, Rodrigo Domiciano Cardoso, Clovis Rodrigo Braz Pereira da Silva, Gabriel Costa Almeida, Bruno Gianordoli Biondi, and Ricardo Kaempf Oliveira. "Ulna Shortening Osteotomy Combined Arthroscopy augmentation for Ulnar Impaction Syndrome: A prospective Analysis." Revista Iberoamericana de Cirugía de la Mano 51, no. 01 (2023): e010-e015. http://dx.doi.org/10.1055/s-0043-1769600.
Full textAbstract:
Resumén Objetivo Este estudio tuvo como objetivo mostrar los resultados clínicos y reportados por los pacientes obtenidos con osteotomía de acortamiento cubital (OAC) combinada con artroscopia en síndromes de impactación cubital (SIC) en pacientes activos. Materiales y Métodos En este estudio clínico prospectivo, se asignó a 13 pacientes a someterse a osteotomía de acortamiento cubital (OAC) definitiva combinada con artroscopia para el síndrome de impactación cubital (SIC). La fuerza de agarre, el rango de movimiento (ROM), la medida de resultado de discapacidades del brazo, el hombro y la mano (QuickDASH), la puntuación de la escala analógica visual (EVA) para el dolor y las características radiográficas se evaluaron a los 6 y 12 meses. Descripción de la técnica Se utiliza una incisión longitudinal para exponer el cúbito. Se preperfora un sistema de acortamiento de cúbito específico para realizar osteotomías separadas por la longitud de acortamiento deseada. Posteriormente, realización de artroscopia de muñeca para realizar técnica de microfractura en el semilunar, piramidal, cabeza de cúbito con punción específica (Chondro Pick,20° by Arthrex®, Na-ples,USA). Se reparó complejo del fibrocartílago triangular (CFCT) y lunopiramidal (LP). Resultados EVA 2.77. La media de QuickDASH fue de 4. Dos pacientes presentaron retraso en la consolidación y se resolvieron con tratamiento no quirúrgico. Conclusión Se encontró que la OAC con artroscopia es un método de tratamiento definitivo, seguro y confiable para SIC en pacientes activos. Los resultados de la EVA y la fuerza de prensión predicen la restauración de la capacidad de los pacientes activos para realizar las actividades de la vida diaria (AVD) de forma independientes.
37
Tiwari, Sonal, Gourab Dey, Gaurav Joshi, Amar Agarwal, Jakob Wilk, and K. K. Agarwal. "Direction of Impact at Lonar Crater, India: Results from Microfracture Density and X-Ray Diffraction Analysis." Journal Of The Geological Society Of India 101, no. 4 (2025): 453–60. https://doi.org/10.17491/jgsi/2025/174116.
Full textAbstract:
ABSTRACT Oblique impacts significantly influence the cratering processes. It causes an asymmetrical crater morphology. In the downrange, it leads to farther distribution of the ejecta blanket and higher shock pressures, which causes more intense deformation and concentric deviation in linear structures. Based on the fact that attenuation of the shock wave and corresponding strain is not uniform in an oblique impact, this study uses the microfracture density and X-ray diffraction (XRD) spectra of the basalts from the crater wall and rim of Lonar crater to determine the possible impact direction. The density of intergranular microfractures in plagioclase and the full width at half maxima (FWHM) of pyroxene (2¯21), plagioclase (040) and magnetite (311) peaks are determined. The microfracture density represents the intensity of brittle deformation, while the changes in XRD spectra relate to the lattice deformation. Both these techniques have proven sensitivity even at low dynamic stress. Our XRD analysis does not present any perceptible trend of FWHM. They are probably affected by post-impact hydrothermal alteration. Notably, the microfracture density is higher in the samples from the southern part of the crater, thus indicating that the damage is higher in the southern part of the crater rim. The study concludes that the probable direction of impact for the Lonar crater is north to south.
38
Nohara, Tsuyoshi, Masaoki Uno, and Noriyoshi Tsuchiya. "Enhancement of Permeability Activated by Supercritical Fluid Flow through Granite." Geofluids 2019 (August 4, 2019): 1–16. http://dx.doi.org/10.1155/2019/6053815.
Full textAbstract:
This geological study utilized electron probe microanalysis of granitic rocks to evaluate traces of hydrothermal fluid activity. Amphibole-plagioclase thermometry was applied to estimate the temperature of a glassy vein as approximately 700°C. The results of mesoscopic and microscopic observations of the rock core obtained through borehole investigations revealed that the track of supercritical fluid flow was microfracture filling with hornblende and plagioclase. Grain-boundary microfractures and parallel microfractures were recognized as traces formed by the limited activity of the supercritical fluid immediately after granite setting in the Late Cretaceous. The current high permeability of a borehole in and around the track of supercritical fluid flow was recognized to be related to the microfracture network. In order to investigate the enhancement of permeability activated by the supercritical fluid flow through granite, the results of this geological study and existing data from in situ permeability tests were analysed. Various fractures in and around the trace of a self-sealing zone were investigated for another borehole rock core. The trace of the self-sealing zone, which was composed of filling textures associated with the supercritical fluid, corresponded to the current low-permeability section of the borehole. Representative types were proposed for simple classification based on the characteristics of fractures and the permeability data of each test section. A high-angle fracture of chlorite filling in combination with an open fracture and the development of a sericite-filling fracture network including a low-angle open fracture were recognized as characteristics of high-permeability types. The results of this study indicate that the enhancement of permeability was activated by supercritical fluid flow through granite.
39
Tuca, María, Tomás Pineda, Javier Oyarce, Felix Etchegaray, and David Figueroa. "Valor diagnóstico de las clasificaciones outerbridge e ICRS para la clasificación artroscópica de lesiones condrales de rodilla." Revista Chilena de Ortopedia y Traumatología 61, no. 02 (2020): 053–59. http://dx.doi.org/10.1055/s-0040-1713381.
Full textAbstract:
Resumen Objetivos Determinar el rendimiento de las clasificaciones de Outerbridge (OB) e International Cartilage Repair Society (ICRS). Método Estudio de test diagnóstico, diseño y recolección de datos prospectivo. Siete traumatólogos sub-especialistas observaron un mismo video donde se exponían 30 lesiones condrales bajo visión artroscópica, para luego clasificarlas según OB e ICRS y consignar el tratamiento de elección para cada una de las lesiones, eligiendo entre 6 alternativas: observación, debridamiento mecánico o térmico, microfractura, OATS o terapias biológicas. Tras 7 días, los evaluadores debían repetir el mismo procedimiento. Resultados La concordancia entre los observadores fue débil para clasificación de ICRS (k 0,25 p < 0,001) y moderada para la clasificación de OB (k 0,45 p < 0,001). La concordancia intra-observador para ICRS oscilaba entre moderada y excelente (k promedio de 0,67), y para la clasificación de OB entre buena y excelente (k promedio 0,83). Ninguna de las dos clasificaciones mostró correlación con la experiencia del cirujano. En la elección de tratamiento, la concordancia entre observadores fue débil (k 0,33 p < 0,001), sin embargo, la concordancia intra-observador fue en todos los casos buena o excelente (k 0,82), mostrando una correlación directamente proporcional a la experiencia del cirujano. La capacidad de discriminación terapéutica, evaluada mediante una regresión logística, mostró un área bajo la curva roc en el rango del no-efecto. Conclusión Ambas clasificaciones mostraron una baja correlación inter-observador y una elevada concordancia intra-observador. En ambas categorías, Outerbridge fue más concordante que ICRS. En cuanto al tratamiento, ninguna de las dos clasificaciones logra unificar criterios quirúrgicos. Nivel de evidencia Nivel I (test diagnóstico).
40
Krakowski, Przemysław, Robert Karpiński, Ryszard Maciejewski, Józef Jonak, and Andrzej Jurkiewicz. "Short-Term Effects of Arthroscopic Microfracturation of Knee Chondral Defects in Osteoarthritis." Applied Sciences 10, no. 23 (2020): 8312. http://dx.doi.org/10.3390/app10238312.
Full textAbstract:
Purpose: The purpose of this study was to estimate the effect of platelet-rich plasma (PRP) augmentation in microfractures of chondral lesions in elderly individuals. Methods: 29 patients with knee osteoarthritis were enrolled in the single-blinded randomized study. The study group consisted of 16 patients and 13 were in the control group. All surgeries were performed in the same manner. The PRP injection was made in a dry arthroscopy directly over the microfractures. The evaluation was performed preoperatively on the 6th, 12th, and 24th week following the surgery. WOMAC and Lysholm questionnaires were utilized. Results: Microfracturation showed WOMAC improvement in the PRP group (p = 0.0012) and in the control group (p = 0.0042). No statistically significant differences between the two groups (p = 0.698) have been found. Clinical improvement was noted in the first six weeks after which the effect lasted. In addition, Lysholm score showed no significant differences at the end of the follow-up between both groups (p = 0.941). Conclusions: Arthroscopic microfracture improves motor function and reduces pain in patients over 50 years old. PRP augmentation of the procedure is safe, and can accelerate and prolong the therapeutic effect of treatment. Excellent effects of the procedure are observed in the first six weeks, after which the improvement lasts.
41
Ling, Bowen, Hasan J. Khan, Jennifer L. Druhan, and Ilenia Battiato. "Multi-Scale Microfluidics for Transport in Shale Fabric." Energies 14, no. 1 (2020): 21. http://dx.doi.org/10.3390/en14010021.
Full textAbstract:
We develop a microfluidic experimental platform to study solute transport in multi-scale fracture networks with a disparity of spatial scales ranging between two and five orders of magnitude. Using the experimental scaling relationship observed in Marcellus shales between fracture aperture and frequency, the microfluidic design of the fracture network spans all length scales from the micron (1 μ) to the dm (10 dm). This intentional `tyranny of scales’ in the design, a determining feature of shale fabric, introduces unique complexities during microchip fabrication, microfluidic flow-through experiments, imaging, data acquisition and interpretation. Here, we establish best practices to achieve a reliable experimental protocol, critical for reproducible studies involving multi-scale physical micromodels spanning from the Darcy- to the pore-scale (dm to μm). With this protocol, two fracture networks are created: a macrofracture network with fracture apertures between 5 and 500 μm and a microfracture network with fracture apertures between 1 and 500 μm. The latter includes the addition of 1 μm ‘microfractures’, at a bearing of 55°, to the backbone of the former. Comparative analysis of the breakthrough curves measured at corresponding locations along primary, secondary and tertiary fractures in both models allows one to assess the scale and the conditions at which microfractures may impact passive transport.
42
Krishnaswamy, Vignesh, Jayachandran Dorairaj, Srilekha Gunasekaran, Sayee Ganesh, Kesavan Priya, and Kurinchichelvan Ramalingam. "Comparative evaluation of morphological and chemical characteristics of bone after performing osteotomy with a piezoelectric device, hard tissue laser, and low-speed handpiece." European Journal of Clinical and Experimental Medicine 23, no. 1 (2025): 70–75. https://doi.org/10.15584/ejcem.2025.1.11.
Full textAbstract:
Introduction and aim. Osteotomy procedures play a crucial role in achieving the desired osseous contour and elimination of the pocket. Traditional instruments such as chisels, files, and rotating burs have limitations including heat generation and tissue dam age. Novel instruments like piezoelectric and hard tissue lasers offer potential advantages in terms of precision and reduced tissue trauma. The aim of this study was to compare the chemical and morphological characteristics of bone surfaces after osteotomy procedures performed with three different instruments: piezoelectric, hard tissue laser, and low-speed handpiece. Material and methods. Fifteen fresh cadaver bone specimens were randomly assigned to three groups: group A (piezoelectric), group B (hard tissue laser) and group C (low-speed handpiece). Osteotomy procedures were performed according to standard ized protocols. The specimens were determined under an energy-dispersive X-ray spectroscopy. Results. Analysis of morphological and chemical characteristics revealed significant differences in bone surface characteristics between groups. Groups A and B exhibited the smoothest surface with minimal tissue damage and microfractures. Group C showed the roughest surface with prominent microfractures and tissue damage. Conclusion. Hard tissue laser and piezosurgery have shown better results due to greater precision as they preserved the bone mor phology, with less microfracture and chemical demineralization after osteotomy preparation compared with low-speed handpiece.
43
Swanson, Erika, Aviva Sussman, and Jennifer Wilson. "Rapid clay precipitation in explosion-induced fractures." Geology 47, no. 12 (2019): 1176–80. http://dx.doi.org/10.1130/g46957.1.
Full textAbstract:
Abstract Fractures within the earth control rock strength and fluid flow, but their dynamic nature is not well understood. As part of a series of underground chemical explosions in granite in Nevada, we collected and analyzed microfracture density data sets prior to, and following, individual explosions. Our work shows an ∼4-fold increase in both open and filled microfractures following the explosions. Based on the timing of core retrieval, filling of some new fractures occurs in as little as 6 wk after fracture opening under shallow (<100 m) crustal conditions. These results suggest that near-surface fractures may fill quite rapidly, potentially changing permeability on time scales relevant to oil, gas, and geothermal energy production; carbon sequestration; seismic cycles; and radionuclide migration from nuclear waste storage and underground nuclear explosions.
44
Albright, Jay C., and Ariel Kiyomi Daoud. "Microfracture and Microfracture Plus." Clinics in Sports Medicine 36, no. 3 (2017): 501–7. http://dx.doi.org/10.1016/j.csm.2017.02.012.
Full text
45
Borodi, Paul-Gabriel, Octav Marius Russu, Andrei Marian Feier, Vlad Alexandru Georgeanu, Sándor-György Zuh, and Tudor Sorin Pop. "Is Microfracture Alone Enough?" Applied Sciences 11, no. 16 (2021): 7309. http://dx.doi.org/10.3390/app11167309.
Full textAbstract:
The technique of microfracture (MFX) was first performed 40 years ago and served for many years as the main procedure for repairing cartilage defects. There is a need to improve microfractures because the regenerated cartilage differs from the original histological aspect; it is less hyaline and more fibrocartilaginous. In addition, and more importantly, the benefits do not persist and the long-term results are unsatisfactory. Adjunctive treatments include platelet-rich plasma (PRP), cell-free-based scaffolds, adipose-derived mesenchymal stem cells (ADSCs), and bone marrow aspirate concentrate (BMAC). The aim of this review was to provide an overview and a perspective of the available data regarding MFX and the principal adjunctive treatments from recent years and also to challenge the traditional MFX procedure. We found that cell-free scaffolds, platelet-rich plasma, and bone marrow aspirate concentrate, although they are relatively novel therapies, showed great potential and maintained their clinical benefits for longer periods of time compared to microfracture alone. As for chitosan-based therapy and adipose-derived mesenchymal stem cells, we were not able to form a definitive conclusion. We believe that the available data show promising results, and future research should be done on each topic discussed. Moreover, investigators involved in bone marrow stimulation techniques should focus on conducting prospective comparative studies, performing second-look arthroscopy, and rely on a single enhancement procedure that can be adequately compared with MFX alone.
46
WANG, SHIFANG, TAO WU, XIUYING CAO, QIUSHA ZHENG, and MIN AI. "A FRACTAL MODEL FOR GAS APPARENT PERMEABILITY IN MICROFRACTURES OF TIGHT/SHALE RESERVOIRS." Fractals 25, no. 03 (2017): 1750036. http://dx.doi.org/10.1142/s0218348x17500360.
Full textAbstract:
The investigation of gas transport in microfractures of tight/shale reservoirs can provide potential applications in predicting shale gas production rates. In this paper, analytical expressions for flow rate and apparent permeability are derived based on the fractal theory and the superposition of convection and molecular diffusion transfer. The proposed model relates the flow rate and apparent permeability to the microstructural parameters of tight/shale reservoirs, gas properties, the ambient pressure as well as temperature. The model predictions from the present model are compared with existing experimental data sets and are found to be consistent with existing experimental measurements. The effects of microstructural parameters of tight/shale reservoirs on apparent permeability are also investigated. The results show that apparent permeability increases with temperature, the pore area fractal dimension, the porosity as well as the maximum microfracture width and decreases with the tortuosity fractal dimension and the mean pressure.
47
Lin, Xiao, Liu Xue-wei, Shao Long-kan, et al. "The study on experimental method of fluid stress sensitivity of low permeability in tight reservoir." Journal of Petroleum Exploration and Production Technology 11, no. 6 (2021): 2599–608. http://dx.doi.org/10.1007/s13202-021-01187-1.
Full textAbstract:
AbstractAccording to the industry standard, low permeability and tight reservoir are highly stress-sensitive in laboratory tests. However, this phenomenon has not been effectively confirmed in the field production test. For this reason, a method to measure stress sensitivity by axial loading is proposed. By loading fixed axial stress, the measurement method achieves the effect of equivalent preloading fluid pressure. Meanwhile, the equivalent theoretical curve can be obtained by translating the curve. Through this method, the stress sensitivity of the core with microfracture is studied. According to the results, the stress sensitivity of the cores can be divided into two stages: the first stage is the non-opening stage of microfractures, in which the stress sensitivity is weak; the second stage is the opening stage of microfractures, in which the stress sensitivity increases sharply. When the permeability changes significantly, the corresponding pressure is the microfracture's opening pressure. In addition, if the abscissa of the experimental results corresponds to the field production data, the field stress sensitivity curve of the field reservoir can be obtained. Conventional stress sensitivity test shows that the four cores in the study block exhibit medium to strong stress sensitivity. According to the stress sensitivity curve analysis after curve translation, the stress sensitivity of the reservoir is about 25% in the elastic production stage, which is classified as weak stress sensitivity. This conclusion can effectively support the phenomenon of the unobvious stress sensitivity in the field production of low permeability and tight reservoirs.
48
Costa-Paz, Matias, Juan Pablo Zicaro, and Carlos Yacuzzi. "Autologous Collagen-Induced Chondrogenesis Technique for Knee Chondral Lesions." Orthopaedic Journal of Sports Medicine 5, no. 1_suppl (2017): 2325967117S0002. http://dx.doi.org/10.1177/2325967117s00028.
Full textAbstract:
Objectives: The purpose of the study was to evaluate a series of patients with osteochondral lesions who underwent a microfractures treatment and autologous collagen-induced chondrogenesis technique (ACIC). Methods: Microfracture treatment and ACIC was performed in eight patients with grade IV cartilage lesion of more than 3 cm2 long. Two patients were discarded due to short follow-up. Four women and two men were evaluated with 50 year-old mean age. The average follow-up was 12.5 months. An associated valgus osteotomy was performed in two patients. Patients were evaluated using the Lysholm score and IKDC. Radiographs were evaluated and a Magnetic Resonance (MRI) was performed in 3 patients. Results: Six patients were evaluated with a 1 B, 2 C and 3 D arthrosis grade according to IKDC classification. Atelocollagen was placed in the medial femoral condyle in four patients (2 associated to tibial valgus osteotomy), in the trochlea in one patient and in both in one patient. Pre and post operative average score IKDC was 38/58 and Lysholm 34/89. One case of postoperative artrofibrosis was registered which was mobilized under anesthesia with satisfactory results. The MRI showed signal with coverage of the chondral defect in more than 70%. There were no cases of infection or reactive synovitis. Conclusion: Atelocollagen combined with microfractures improved the clinical conditions in patients with articular cartilage lesions of the knee. It is necessary more patients and longer follow-up to verify this data.
49
Maji, A. K., C. Ouyang, and S. P. Shah. "Fracture mechanisms of quasi-brittle materials based on acoustic emission." Journal of Materials Research 5, no. 1 (1990): 206–17. http://dx.doi.org/10.1557/jmr.1990.0206.
Full textAbstract:
Recently acoustic emission (AE) techniques have been used to study crack propagation in materials. The application of these techniques to heterogeneous, quasi-brittle materials such as concrete requires a better understanding of how the signal generated from a microfracture is transformed due to wave propagation and due to the transducer response. In this study, piezoelectric transducers were calibrated using displacement transducers. The validity of an elastodynamic Green's function approach was examined for cement-based materials. The acoustic emission source was characterized using moment tensor analysis. Acoustic emission measurements were analyzed for center-cracked-plate specimens of mortar and concrete. It was observed that, as expected, the dominant mode of cracking was mode I (tensile). However, mode II (shear) and mixed mode cracks also occurred, perhaps due to grain boundary sliding and interface debonding. Microfractures appear to localize prior to critical crack propagation. Mode I cracks generally required more energy release than mode II and a smaller inclusion provided a stronger interface bond than the larger ones.
50
Zhao, Conghui, Dong Wu, Fengbo Hu, Meng Sun, Tao Li, and Hu Wang. "Quantitative Characteristics of Micro Bedding Fractures in the Wufeng–Longmaxi Formation Based on High-Resolution Map Imaging Technology." Processes 11, no. 7 (2023): 1942. http://dx.doi.org/10.3390/pr11071942.
Full textAbstract:
The study of microfractures in shale is mainly based on qualitative description. Conversely, quantitative description of the parameters of shale microfractures can provide a quantitative basis for shale fracture characterization and shale physical properties. Nine shale reservoir samples of the Wufeng–Longmaxi Formation in the Jiaoshiba area were studied, using the backscattered two-dimensional multiscale resolution imaging technology, combined with high-resolution map imaging technology (MAPS), and thousands of images were obtained using scanning electron microscopy. Gray image analysis was used to extract microfracture information from images (2 × 2 cm multiresolution). The “maximum circle method” was used to calculate the length and aperture characteristics of the fractures. Parameters such as the area of the bedding fractures, the surface rate of the fractures, and the linear density of the fractures were obtained by the integration of apertures. The fracture length was between 2~7 mm, the aperture was between 1~6 μm, the linear density was between 1~6/m and the surface rate was 1%. The bedding fractures do not contribute much to the porosity of the shale reservoir; however, shale reservoirs with high porosity have a high development of bedding fractures and good permeability. The development of a bedding fracture is controlled by the lithology within shale reservoirs. Different types of lithology contain different bedding fractures, but they have a certain regularity. Moreover, the content of organic matter and TOC (total organic content) in the shale reservoir control the development of a bedding fracture, where a high organic and TOC content are accompanied by a high number of fractures.