Mancos Formation
Quantifying the influence of clay-bound water on wave dispersion and attenuation signatures of shale: An experimental study
Long, Teng (University of Houston) | Qin, Xuan (University of Houston) | Wei, Qianqian (University of Houston) | Zhao, Luanxiao (Tongji University) | Wang, Yang (University of Houston) | Chen, Feng (University of Houston) | Myers, Michael T. (University of Houston) | Zheng, Yingcai (University of Houston) | Han, De-Hua (University of Houston)
ABSTRACT Understanding the elastic and attenuation signatures of shales is of considerable interest for unconventional reservoir characterization and sealing capacity evaluation for CO2 sequestration and nuclear waste disposal. We have conducted laboratory measurements on seven shale samples at seismic frequencies (2–100 Hz) to study the effects of clay-bound water (CBW) on their wave dispersion and attenuation signatures. With nuclear magnetic resonance and a helium porosimeter, the volume of CBW in the shale samples is quantified. The forced-oscillation measurement reveals that Young’s modulus exhibits a continuous dispersion trend from 2 to 100 Hz. The extensional attenuation () shows a weak frequency and pressure dependence on effective pressure ranging from 5 to 35 MPa. The magnitude of extensional attenuation shows a positive correlation with CBW, with an value of 0.89. It is found that 4% of CBW in the rock frame causes approximately a 5% modulus increase from 2 to 100 Hz. We adopt a constant model for assigning frequency-dependent bulk and shear moduli to the CBW in the rock-physics modeling, which can fit the experimental data of modulus dispersion and attenuation well, indicating that the bulk and shear moduli of CBW in shales might behave viscoelastically.
- Research Report > New Finding (0.50)
- Research Report > Experimental Study (0.40)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Mineral > Silicate (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (0.67)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale gas (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
Unconventional Reservoirs: Contact Area and Fracture Network Resulting from Perforations in Shale. A Comparative Study of Different Shale Targets and Shaped Charge Designs Optimized for Hydraulic Fracturing
Loehken, J. (DynaEnergetics Europe GmbH, Troisdorf, Germany) | McNelis, L. (DynaEnergetics Europe GmbH, Troisdorf, Germany) | Yosefnejad, D. (DynaEnergetics Europe GmbH, Troisdorf, Germany) | Will, D. (DynaEnergetics Europe GmbH, Troisdorf, Germany)
Abstract After decades of a continuous improvement of the plug and perf technology for horizontal wells and especially the shaped charges employed, operators nowadays have the choice between a variety of shaped charge designs. As a guidance to choose the optimal charge, this snapshot examines the influence of shale rock type and shaped charge design on the tunnel created in the reservoir rock during perforation. Tests were conducted in an API Section II Test environment, simulating in-situ downhole conditions. Specifically, the investigation focused on the characteristics of the contact surface and the induced fracture network resulting from different perforation charges, each with its own distinctive tunnel geometry. Three different shaped charge designs were tested on various shale targets. This included equal entrance hole charges, maximum formation contact, and oriented perforation tailored charges. To assess the impact of the formation rock on the results, test shots were made on Marcellus, Mancos, and Lotharheiler, which is similar to the Haynesville or Eagle Ford, shale cores. The analysis included CT scans to identify tip fractures and to examine the shape of the tunnel as well as conventional core analysis. Additionally, newly formed fractures within the rock and on the surface of the perforation tunnel were identified. The test results indicate that both the charge type and the rock type significantly influence the tunnel geometry and fracture network. Although all charges created roughly the same entrance hole diameter in the casing, variations in tunnel length and contact surface as well as in the newly created fractures were observed. Notably, the shape of the tunnel deviated strongly from the theoretical assumed cylindrical or conical tunnel. Doglegs, as well as cavities were detected at many tunnel tips, which change the overall stress field at the tunnel wall. To determine which rock parameters are relevant, the cores underwent analysis in an external laboratory to assess their petrophysical properties for further correlation analysis. From a practical perspective shale rock proved to be a challenging target rock due to its high anisotropy and significant differences in rock strength between targets of the same formation. Additionally, the target cores were prone to cracking during the rock preparation process. Therefore, this study should be considered as a snapshot and conclusions drawn from this set of tests should be approached cautiously and account for these circumstances. Our study provides insights into the dependency of the perforation result on the type of shale and charge design. Depending on the combination of the perforation technique and the characteristics of the rock formation, distinct fracture networks and tip deviations are formed. This improved understanding will help to identify the best perforation strategy tailored to the specific reservoir rock's unique properties.
- North America > United States > Texas (1.00)
- Europe (1.00)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Texas > West Gulf Coast Tertiary Basin > Eagle Ford Shale Formation (0.99)
- (18 more...)
Frequency-dependent elastic properties of fracture-induced VTI rocks in a fluid-saturated porous and microcracked background
Wang, Wenhao (China University of Petroleum (East China)) | Li, Shengqing (China University of Petroleum (East China), Laoshan National Laboratory) | Guo, Junxin (Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology, Southern University of Science and Technology) | Zhang, Chengsen (PetroChina Tarim Oilfield Company) | Duan, Wenxing (PetroChina Tarim Oilfield Company) | Su, Yuanda (China University of Petroleum (East China), Laoshan National Laboratory) | Tang, Xiao-Ming (China University of Petroleum (East China), Laoshan National Laboratory)
Fractures are widely distributed underground. The stiffness matrix of fractured rocks has been extensively investigated in a fluid-saturated porous background medium. However, the existing stiffness models only incorporated the attenuation mechanism of wave-induced fluid flow (WIFF). For macroscopic fractures, the elastic scattering (ES) of fractures cannot be ignored. To alleviate this issue, a frequency-dependent stiffness matrix model was developed, including the mesoscopic wave-induced fluid flow between fractures and background (FB-WIFF), the microscopic squirt flow, and the macroscopic ES from the fractures. By combining the far-field scattered wavefields of normal incident P and SV waves with the linear slip theory, the dynamic full-stiffness matrices for fracture-induced effective VTI rocks in a fluid-saturated porous and microcracked background were derived. Then, the P, SV, and SH wave velocities and attenuation can be obtained through the Kelvin-Christoffel equation. The results indicate that the FB-WIFF mechanism significantly affects the velocities and attenuation of the P and SV waves, but has nearly no effect on the SH wave, while the squirt flow and ES mechanisms affect the velocities and attenuation of both the P, SV, and SH waves. For validation, the model was compared with existing models and previous experimental ultrasonic data.
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- Asia > China > Xinjiang Uyghur Autonomous Region > Tarim Basin (0.99)
- Asia > China > Sichuan > Sichuan Basin (0.95)
The main controlling factors of tensile strength in sight of shale reservoir under horizontal bedding: Example of the Lower Paleozoic Niutitang Formation shale from Micangshan, China
Li, Delu (Xi’an University of Science and Technology, Ministry of Natural Resources, Xi’an University of Science and Technology) | Li, Haibin (Xi’an University of Science and Technology, Ministry of Natural Resources, Xi’an University of Science and Technology) | He, Qianyang (Xi’an University of Science and Technology, Ministry of Natural Resources, Xi’an University of Science and Technology) | Gao, Jianwen (PetroChina Changqing Oilfield Company) | Tao, Wenxing (SINOPEC) | Wang, Shimiao (SINOPEC)
Abstract Understanding the mechanical characteristics of marine shale during fracturing is essential for shale gas development, and its core scientific problem is what factors in shale control its mechanical properties. The 12 shale samples from the Lower Paleozoic Niutitang Formation in Micangshan are tested for tensile strength and examined using X-ray diffraction, low-field nuclear magnetic resonance (NMR), EA2000 elemental analyzer, and scanning electron microscopy to explore the main controlling factors of shale tensile strength under horizontal bedding conditions. The findings are as follows. (1) The tensile strength of the shale is relatively high, ranging from 10.05 MPa to 20.34 MPa. Quartz is the largest proportion of the shale minerals, accounting for 53.2 wt%–59.0 wt%, followed by anorthose and clay minerals. Total organic carbon (TOC) concentration ranges from 1.7 wt% to 4.1 wt%. (2) NMR results indicate that the pore structure of shale is mainly mesoporous, accounting for 75.76%–88.03%, followed by macropores (12.57%–21.24%) and micropores (0.68%–4.91%). Low-pressure nitrogen adsorption and desorption results indicate that the average pore diameter of shale is 12.58–16.02 nm, which is basically consistent with NMR results. The negative correlation between fractal dimension and tensile strength indicates that the higher the tensile strength of the shale, the lower the complexity of its seepage pores. (3) Micropores occur mainly in clay minerals, whereas quartz indicates positively correlation with mesoporous content. The higher the proportion of mesopores, the lower the tensile strength. This indicates that the mesopores are the main factor controlling the tensile strength, and the quartz content in minerals is a secondary factor restricting the tensile strength. TOC has little controlling action on the tensile strength. This contribution provides a theoretical basis for shale fracturing.
- Asia > China > Sichuan Province (0.47)
- Asia > China > Shaanxi Province (0.46)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Mineral (1.00)
- Materials (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > Asia Government > China Government (0.46)
- North America > United States > West Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Virginia > Appalachian Basin > Marcellus Shale Formation (0.99)
- North America > United States > Pennsylvania > Appalachian Basin > Marcellus Shale Formation (0.99)
- (13 more...)
Integrating Embedment and Creep Behavior for Multisize Proppant in Shale: Conceptual Model and Validation
Cheng, Qiaoyun (Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education, School of Earth Resources, and Hubei Key Laboratory of Marine Geological Resources, China University of Geosciences) | Zhou, Sandong (Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education, School of Earth Resources, and Hubei Key Laboratory of Marine Geological Resources, China University of Geosciences (Corresponding author)) | Li, Bobo (College of Mining, Guizhou University) | Pan, Zhejun (Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development, Ministry of Education, Northeast Petroleum University) | Liu, Dameng (Coal Reservoir Laboratory of National Engineering Research Center of CBM Development & Utilization, School of Energy Resources, China University of Geosciences) | Yan, Detian (Key Laboratory of Tectonics and Petroleum Resources of the Ministry of Education, School of Earth Resources, China University of Geosciences)
Summary The embedment of multisize proppant in fractures and the creep behavior of the shale will affect fracture permeability, yet the combination of the two factors has not been well studied and understood. In this work, the impact of graded arrangement of multisize proppant on fracture permeability is studied considering proppant embedment and shale creep in a hydraulic fracture. The Hertz contact theory is used to quantify the depth of embedment for proppant with different particle sizes, and the Burgers model is used to describe the creep behavior of shale. Then, a permeability model considering the effects of multisize proppant embedment with shale creep is developed and verified. The results show that, under the combined effect of shale creep and proppant embedment, the reduction in permeability of the proppant arrangement with equal amount of three particle sizes is about twice that of two particle sizes. It also shows that there is an optimal Young’s modulus ratio that allows for minimal proppant embedment when the Young’s moduli of proppant and shale are in the same order of magnitude. Moreover, creep is positively correlated with loading pressure, loading time, and clay mineral content in the shale and there is a clear correspondence between shale creep, fracture width, and permeability variation. It is suggested that proppant type, size, mixing ratio, and fracturing parameters for shale reservoirs should be optimized by combining reservoir mineralogy and rock mechanics to reduce the cumulative effect of shale creep on long-term productivity. This work is useful for optimizing the hydraulic fracturing design for shale reservoirs and improving the efficiency of hydraulic fracturing to increase permeability.
- Asia > China (1.00)
- North America > United States > Texas (0.93)
- Research Report > New Finding (0.66)
- Research Report > Experimental Study (0.66)
- South America > Argentina > Patagonia > Neuquén > Neuquen Basin > Vaca Muerta Shale Formation (0.99)
- North America > United States > Texas > West Gulf Coast Tertiary Basin > Eagle Ford Shale Formation (0.99)
- North America > United States > Texas > Sabinas - Rio Grande Basin > Eagle Ford Shale Formation (0.99)
- (6 more...)
QUANTIFYING THE INFLUENCE OF CLAY-BOUND WATER ON WAVE DISPERSION AND ATTENUATION SIGNATURES OF SHALE: AN EXPERIMENTAL STUDY
Long, Teng (University of Houston) | Qin, Xuan (University of Houston) | Wei, Qianqian (University of Houston) | Zhao, Luanxiao (Tongji University) | Wang, Yang (University of Houston) | Chen, Feng (University of Houston) | Myers, Michael T. (University of Houston) | Zheng, Yingcai (University of Houston) | Han, De-Hua (University of Houston)
Understanding the elastic and attenuation signatures of shales is of considerable interest for unconventional reservoir characterization and sealing capacity evaluation for CO2 sequestration and nuclear waste disposal. We conducted laboratory measurements on seven shale samples at seismic frequencies (2100 Hz) to study the effects of clay-bound water (CBW) on their wave dispersion and attenuation signatures. With Nuclear Magnetic Resonance (NMR) and helium porosimeter, the volume of CBW in the shale samples is quantified. The forced-oscillation measurement reveals that Youngs modulus exhibits a continuous dispersion trend from 2 to 100 Hz. The extensional attenuation shows a weak frequency- and pressure-dependence on effective pressure ranging from 5 to 35 MPa. The magnitude of extensional attenuation shows a positive correlation with CBW, with an R-square value of 0.89. It is found that 4% of CBW in the rock frame causes roughly a 5% modulus increase from 2 to 100 Hz. We adopt a constant Q model for assigning frequency-dependent bulk and shear moduli to the CBW in the rock physics modeling, which can fit the experimental data of modulus dispersion and attenuation well, indicating that both the bulk and shear moduli of CBW in shales might behave viscoelastically.
- Research Report > New Finding (0.50)
- Research Report > Experimental Study (0.40)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock > Mudrock > Shale (1.00)
- Geology > Mineral > Silicate (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Interpretation (0.67)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- Reservoir Description and Dynamics > Unconventional and Complex Reservoirs > Shale gas (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- (2 more...)
Permeability Dependence of a Sand Packed Tube on the Type of Fluid and Grains Sorting
Sagirov, R. N. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Bolotov, A. V. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Varfolomeev, M. A. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Derevyanko, V. K. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Tazeev, A. R. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Minkhanov, I. F. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Tuktarov, R. F. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation) | Demchenkov, D. V. (Department of reservoir engineering, Kazan Federal University, Kazan, Russian Federation)
Abstract Rock permeability depends on the type of a fluid, the type of a reservoir, and many other factors. The object of study was a sand packed tube with sieved sand, which was affected by a hydraulic press with different loads In this article, the authors described the dependence of several parameters on the sorting of grains and a correlation coefficient determined: for absolute gas permeability – 0.964, porosity −0.958, permeability for distilled water −0.935, permeability for highly mineralized water −0.935, phase permeability and displacement efficiency. The results of the research show a direct dependence of all the parameters on the sorting of grains. The distraction of grains under different loads was shown by microscopic and sieve analysis. With increasing of load the content of less-size grains increases from 0 to 14 per cent. During the experiment, an effect was observed that had never been previously described in literature. The effect is that once the maximum destruction of the grains has been reached, the permeability of distilled water becomes higher than the permeability of mineralized water difference in permeability is about 60 per cent.
- Research Report > New Finding (1.00)
- Research Report > Experimental Study (1.00)
- Geology > Mineral (0.94)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock (0.93)
- Geology > Geological Subdiscipline (0.68)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- Europe > Russia > Volga Federal District > Tatarstan > Volga Urals Basin > Akanskoye Field (0.99)
Abstract Under the environment of complex wellbore trajectory, deviated wells, or lateral drilling, be it for oil and gas, geothermal or carbon-sequestration, the newly developed downhole sensors, data-transmission in real-time together with data-analytics has enabled utilize all information contained in weight-on-bit, rate-of-penetration, rotational speed, torque, effective mud-weight used, and drilling vibrations. The high-resolution drilling data helps us mitigate drilling dysfunction and complement formation logs. In some cases, when conventional log acquisition is not possible, downhole drilling data may become the only source for formation properties. The paper presents our investigations in the standalone use of downhole drilling data. The process evaluates formation properties and integrates with other petrophysical logs to improve real-time data quality and interpretation. Case studies are included from both lab experiments and field examples. The current research efforts are encouraged by technological developments, in downhole sensors, which can now be included with the bottom-hole drilling assembly and used in in-situ acquisition of drilling data. We use downhole drilling data and consider both rule-based and machine-learning (ML) methods, to evaluate formation for lithological and geomechanical heterogeneities. A well from Gulf of Mexico is selected to apply the concept. Results are verified against established log-based formation properties estimation. In wells with high deviations, or complex trajectories, downhole drilling data is found to be more reliable compared to use of similar measurements made at surface followed by surface-to-downhole conversions. In the present work, we trained the system using 75% of downhole drilling data, together with measured vibrational and bending moment. The model was then applied in the remaining 25% of untrained intervals and demonstrated ability to predict formation properties with good correlation. The evaluation was done on memory-based data received after drilling, however, can also be implemented as automatic processing to support real-time operation. Drilling data is always available, whenever a well is being drilled. Real-time formation evaluation, based on this information, provides the drilling engineers and geoscientists an additional resource which can be either standalone or complementary to log data. Downhole drilling data is also available early in time compared to LWD sensors typically placed several tens of feet behind the bit. Ongoing improvements in sensor specifications, data quality and interpretation methods, is promising especially for environments where conventional real-time logging is not feasible. For robust ML application, training data from a range of geographical regions and reservoir is included to ensure correct prediction in all scenarios.
- Geology > Rock Type (1.00)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > Cuba > Gulf of Mexico (0.93)
- (4 more...)
Abstract Microfacies analysis is the first step for depositional environment interpretation and sand body prediction. Textural details from borehole images are building blocks for facies analysis, representing different paleo sediimentation conditions. Associated workflows have been applied on high resolution borehole images by geologists and log analysts manually. Automation via machine learning solutions provides an opportunity to improve the working efficiency and accuracy. Such an approach has given satisfactory results with post-drilling wireline images. In this paper, the improved workflow for sedimentary analysis was applied and validated with a logging-while-drilling (LWD) resistivity imager in oil-based mud environment (OBM). The OBM LWD resistivity image in oil-based mud provides 72 data points at single depth from 4 different frequencies of electromagnetic measurements with a patented processing. The non-gap resistivity image gives more confident texture characterization. The continuous histogram and correlogram derived from image data were used for image segmentation. In each image segmentation, multiple vector properties were extracted from image data representing different texture features including adoptive variogram horizontally. Agglomerative clustering was selected for its stability and repeatability. The internally built dendrogram allows to automatically determine the number of clusters by finding a stable distance between the clusters’ hierarchy branches. In addition to the features extracted from image data, optional petrophysical logs with variable weights may be fed to the algorithm for a better classification. A case study from Gulf of Mexico is being used to demonstrate this workflow with Hi-Res LWD image. More than 10 different sedimentary geometries were classified automatically from image and petrophysical logs. The microfacies were named manually from sedimentary geometries with the related geological concept accordingly. The fluvial channel and delta sedimentary environment were interpretated finally from microfacies association. The interpretation results were compared and validated with published dips-based solution as well. This is the first time for the automatic borehole image segmentation with LWD OBM images. The working efficiency was improved a lot through this workflow and the accuracy of microfacies interpretation was guaranteed by machine learning solution.
- North America > United States > Colorado (0.46)
- North America > United States > Texas (0.28)
- North America > United States > Wyoming > Uinta Basin (0.99)
- North America > United States > Utah > Uinta Basin (0.99)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- (2 more...)
- Well Drilling > Drilling Measurement, Data Acquisition and Automation > Logging while drilling (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Exploration, development, structural geology (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Open hole/cased hole log analysis (1.00)
- Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (1.00)
Deformation, Damage, And Fracture in Hot Dry Rock of Geothermal Reservoir Under Uniaxial and Diametrical Compression Using 3D-DIC
Nath, F. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.) | Aguirre, G. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.) | Vazquez, E. C. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.) | Portillo, O. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.) | Gindic, R. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.) | Cuellar, A. (School of Engineering, Texas A&M International University, Laredo, TX, U.S.A.)
Abstract Geothermal resources have attracted global attention because of their renewability, cleanliness, and universality. The U.S. Department of Energy estimates that harnessing just 0.1% of the Earth's geothermal energy can power humanity for 2 million years. An improved geothermal system (EGS) efficiently extracts heat from deep hot dry rock (HDR). However, EGS is battling to assure safe drilling and appropriate fracturing to extract heat potential. Conventional laboratory techniques cannot detect fine-scale variability in HDR structures during loading. Due to its inherent heterogeneities, it is especially crucial to characterize deformation and frac-face damage during induced fracturingto unlock heat energy from HDR. This study uses three-dimensional digital image correlation (3D-DIC) to examine damage and deformation in HDR samples. HDR samples from the DOE Utah FORGE project's Well 16B(78)-32 were studied under uniaxial and diametrical compression using a precise 100kN electro-mechanical load frame with a continuous displacement of 0.05mm/min. The samples had a wide range of minerals. During the uniaxial and diametrical compression tests, a3D-DIC image capture system was set up to watch the samples without touching them at a rate of 5 frames per second. A black-and-white speckle pattern is affixed to the specimen to monitor its deformation under load. The 3D-DIC system is used for image processing, visualization, and analysis of the HDR damage process under various load circumstances. Our preliminary results of DIC-generated quantitative full-field strain maps (tension, compression, and shear) exhibiting all sequences involved in the damage process of HDR samples. To evaluate the sample damage, damage factors are measured using DIC maps; the tension-compression ratio is obtained at 5%-10%. The damage evolution process of HDR specimens is separated into four stages, which are evaluated by damage variables: initial damage stage, linear elastic, elastic-plastic, and plastic damage stage. The findings have a major impact on our ability to predict the damage process in EGS. DIC outperforms micro-Computed Tomography(µ-CT), Scanning Electron Microscope (SEM), andAcoustic Emission(AE) in terms of test range, affordability, accuracy, and monitoring of the entire field. This method overcomes the laboratory limitations for evaluating HDR damage heterogeneity. This image-based algorithm is better at understanding anisotropic and heterogeneous HDR fragmentation and predicting stimulated reservoir volume (SRV). Thus, the results of this study will enhance the effectiveness of hydraulic fracturing in HDR and heat recovery from EGS.
- North America > United States > Texas (0.46)
- North America > United States > California (0.28)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Mineral > Silicate (0.68)
- Energy > Oil & Gas > Upstream (1.00)
- Energy > Renewable > Geothermal > Geothermal Resource > Hot Dry Rock (0.71)
- North America > United States > New Mexico > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)
- North America > United States > Colorado > San Juan Basin > San Juan Basin Field > Mancos Formation (0.99)