Article
Geosciences, Multidisciplinary
Xinglong Zhao, Bingxiang Huang, Giovanni Grasselli
Summary: The study investigates the mechanism of natural fracture failure induced by disturbing stress using numerical calculation methods. It reveals the shear failure mechanism of natural fractures during hydraulic fracturing and the mechanical changes when hydraulic fracturing approaches natural fractures.
FRONTIERS IN EARTH SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
Bingxiang Huang, Heng Li, Xinglong Zhao, Yuekun Xing
Summary: Traditional hydraulic fracturing theory believes that the breakdown pressure of rock decreases as the initial pore pressure increases. However, previous experimental studies have shown that the breakdown pressure of rock hydraulic fracturing may increase with the increase of initial pore pressure (gradient), which cannot be explained by traditional theory. This study analyzes the pore pressure effect of rock hydraulic fracturing and proposes a new fracture criterion considering the pressure-gradient effect. The results show that the proposed fracture criterion can accurately predict the breakdown pressure of rock, providing a theoretical basis for rock hydraulic fracturing mechanism.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Engineering, Chemical
Qiquan Ran, Xin Zhou, Jiaxin Dong, Mengya Xu, Dianxing Ren, Ruibo Li
Summary: This study establishes a multi-hydraulic fracturing propagation model that considers rock damage, stress, and fluid flow, using the extended finite element method. The effects of horizontal stress difference and cluster spacing on fracture propagation are quantitatively analyzed. The results show that changes in stress difference and inter-cluster spacing significantly influence the final morphology of hydraulic fractures. The study also provides insights into the impact of inter-fracture interference on fracture propagation morphology.
Article
Engineering, Chemical
Yushi Zou, Budong Gao, Qimiao Ma
Summary: This study investigates the fracture propagation behavior during temporary plugging and diverting fracturing (TPDF) in coal formations. The experimental results show that TPDF can improve fracture complexity even under high stress difference. The use of appropriate size and concentration of temporary plugging agent (TPA) can effectively block primary fractures and promote the generation of new fractures.
Article
Mechanics
Feipeng Wu, Xianzhang Fan, De Li, Hongbin Yang, Jing Liu, Xiaojun Li
Summary: The main technology for removing deep plugging in unconsolidated sandstone reservoirs is deep penetrating hydraulic fracturing with chemical treatment. The study analyzed the effects of different viscosities and injection rates on fracture initiation and propagation, finding that high viscosity fracturing fluid at high injection rates can achieve hydraulic fracturing in high-permeability unconsolidated sandstone, and adjusting the viscosity and injection rate slightly higher than the threshold value can generate deep penetrating fractures in unconsolidated sandstones.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Computer Science, Interdisciplinary Applications
Shan Wu, Ke Gao, Yu Feng, Xiaolin Huang
Summary: This paper uses the combined finite-discrete element method (FDEM) to study the interaction mechanism between hydraulic fractures and bedding interfaces. The results show that the slip property of bedding interfaces determines whether hydraulic fractures can cross over, and high permeability only delays the crossing time. Additionally, the slip type and permeability of bedding interfaces can cause changes in hydraulic fracture width and result in a discontinuous distribution of local stress and fluid pressure near bedding interfaces.
COMPUTERS AND GEOTECHNICS
(2022)
Article
Engineering, Geological
Qingwang Cai, Bingxiang Huang, Xinglong Zhao, Yuekun Xing, Shenglong Liu
Summary: The characterization of a real meso-macro hydraulic fracture (HF) network in coal mass using X-ray micro-computed tomography helps to understand its formation mechanism better.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Engineering, Geological
Egor Dontsov
Summary: The purpose of this study is to investigate the morphology of simultaneously propagating hydraulic fractures from a horizontal well. The findings show that stress interaction between the fractures affects their shapes, with different parameters having different impacts.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2022)
Article
Engineering, Environmental
Chao Liu, Dongming Zhang, Honggang Zhao, Minghui Li, Zhenlong Song
Summary: This study investigated the hydraulic fracturing characteristics of elliptical boreholes. It found that the horizontal stress difference and borehole shape together affect the breakdown pressure. The experiments showed that the breakdown pressure decreases with the increase of the short-axis of elliptical boreholes when there is a horizontal stress difference. However, when the horizontal stress difference is zero, the situation is opposite.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2022)
Article
Engineering, Environmental
Amir Mohamadi, Mahmoud Behnia, Mahmoud Alneasan
Summary: The study focuses on determining crustal stress using hydraulic fracturing and fracture mechanics methods, finding that stress magnitudes calculated by fracture mechanics approach are greater than those by classical methods. The research also investigates the impact of crack inclination angle and length on stress magnitudes, and analyzes the distribution of fluid pressure along cracks and its influence on stress intensity factor in crack tips.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2021)
Article
Computer Science, Interdisciplinary Applications
Xiaoying Zhuang, Xinyi Li, Shuwei Zhou
Summary: This study proposes a new 3D phase field model for predicting hydraulic fracture propagation in naturally layered rocks, considering the influence of initial stress field. The research finds that PFM can effectively predict different fracture patterns and guide the application of HF in naturally layered unconventional reservoirs through optimized design.
ENGINEERING WITH COMPUTERS
(2023)
Article
Energy & Fuels
Jie Bai, Xiao-Qiong Wang, Hong-Kui Ge, Hu Meng, Ye-Qun Wen
Summary: Unconventional reservoirs often contain weak surfaces such as faults, laminae, and natural fractures, which can greatly improve extraction efficiency when effectively activated and utilized. This study calculates the hydraulic fracturing-induced stress field and establishes a stability model for natural fractures. Parametric studies are conducted to investigate the impact of each parameter on fracture stability. The validity of the model is verified by comparing it with data from the X-well 150-155 formation in the Songliao Basin. The study suggests connecting natural fractures with hydraulic fractures and then activating the natural fractures to effectively utilize them and form a complex fracture network.
Article
Geochemistry & Geophysics
John W. Cosgrove, Steven G. Banham, Sanjeev Gupta, Robert Barnes
Summary: The aim of this article is to determine the conditions on Mars during the formation of fractures and veins in mudstones in Gale crater and to understand whether these rocks were superficial deposits or have experienced significant burial and compaction. Close-up images of the fracture and vein networks on horizontal bedding planes provide detailed geometry information for fracture analysis and reveal the possible role of high fluid pressures in their formation. The geometry of the veins in a vertical section can indicate the level of compaction and minimum burial depth.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2022)
Article
Mechanics
Zhenghong Chen, Jiadong Qiu, Qiunan Chen, Xibing Li, Binhui Ma, Xiaocheng Huang
Summary: This paper investigates the effects of multi-perforations hydraulic fracturing (MPHF) on stress and fracture characteristics of hard rock mass during excavation in underground engineering. The results show that the MPHF parameters have significant influence on stress distribution and microcrack formation. Careful selection of appropriate MPHF parameters can enhance project economics and performance.
ENGINEERING FRACTURE MECHANICS
(2022)
Article
Materials Science, Multidisciplinary
Jinkui Ma, Hong Li, Xiaomin Guo, Fuchao Tian, Huaiguang Guo
Summary: This study focuses on the treatment of hard roofs in coal mining, aiming to understand the mechanism of crack propagation caused by hydraulic fracturing. The research provides insights into the conditions and parameters for effective control of hard roofs in mines, and has been successfully applied in a coal mine for many years.
FRONTIERS IN MATERIALS
(2022)
Article
Engineering, Geological
Pengcheng Fu, Xin Ju, Jixiang Huang, Randolph R. Settgast, Fang Liu, Joseph P. Morris
Summary: The study suggests that maintaining an open fracture in the carbon storage reservoir requires a continuous increase in pressure, with cooling near the well potentially reducing the fracture-opening pressure. However, the fracture propagation pressure is still dictated by processes in the far-field rock.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Energy & Fuels
J. T. Birkholzer, J. Morris, J. R. Bargar, F. Brondolo, A. Cihan, D. Crandall, H. Deng, W. Fan, W. Fu, P. Fu, A. Hakala, Y. Hao, J. Huang, A. D. Jew, T. Kneafsey, Z. Li, C. Lopano, J. Moore, G. Moridis, S. Nakagawa, V Noel, M. Reagan, C. S. Sherman, R. Settgast, C. Steefel, M. Voltolini, W. Xiong, J. Ciezobka
Summary: This paper introduces a new modeling framework for simulating hydraulic fracturing and production from microscopic to reservoir scales, which combines high-performance simulators and laboratory scale studies. The framework is currently being tested using field data and core samples from the HFTS. This approach aims to incorporate micro-scale processes into reservoir-scale simulations for enhanced accuracy.
Article
Engineering, Civil
Hui Wu, Pengcheng Fu, Joseph P. Morris, Earl D. Mattson, Ghanashyam Neupane, Megan M. Smith, Adam J. Hawkins, Yuran Zhang, Timothy Kneafsey
Summary: This study demonstrates the feasibility of stochastic tracer modeling on a high-fidelity fracture network model, providing important insights into flow and transport characteristics in subsurface fractured reservoirs.
JOURNAL OF HYDROLOGY
(2021)
Article
Engineering, Geological
Hui Wu, Randolph R. Settgast, Pengcheng Fu, Joseph P. Morris
Summary: The study introduces an enhanced VCCT for calculating energy release rates and stress intensity factors for cracks with arbitrary shapes in 3D domains on structured grids. It was implemented into a multiphysics simulation environment capable of simulating crack propagation in the framework of linear elastic fracture mechanics. The enhanced VCCT was validated through comparisons with existing analytical/numerical solutions and other VCCT approaches for SIF calculation along nonsmoothed crack fronts.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Engineering, Geological
Jizhong He, Fang Liu, Gang Deng, Pengcheng Fu
Summary: This study demonstrates that the high-order characteristics of grain size distribution significantly affect the deformation behavior of coarse-grained granular materials. Two proposed grading indices are highly correlated with internal fabric parameters, while conventional coefficient of uniformity is not effective in characterizing high-order features of gradation. Incorporating high-order characteristics of gradation is essential for establishing effective gradation-dependent relations of deformation parameters for polydisperse granular materials.
INTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS
(2021)
Article
Green & Sustainable Science & Technology
Xin Ju, Pengcheng Fu, R. Randolph Settegast, P. Joseph Morris
Summary: The study shows that containing fracturing within the lower portion of the caprock can improve injectivity without compromising overall seal integrity. A simple method has been developed to capture the complex interactions among fluids, fractures, reservoirs, and caprocks.
INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL
(2021)
Article
Geochemistry & Geophysics
Pengcheng Fu, Martin Schoenball, Jonathan B. Ajo-Franklin, Chengping Chai, Monica Maceira, Joseph P. Morris, Hui Wu, Hunter Knox, Paul C. Schwering, Mark D. White, Jeffrey A. Burghardt, Christopher E. Strickland, Timothy C. Johnson, Vince R. Vermeul, Parker Sprinkle, Benjamin Roberts, Craig Ulrich, Yves Guglielmi, Paul J. Cook, Patrick F. Dobson, Todd Wood, Luke P. Frash, Lianjie Huang, Mathew D. Ingraham, Joseph S. Pope, Megan M. Smith, Ghanashyam Neupane, Thomas W. Doe, William M. Roggenthen, Roland Horne, Ankush Singh, Mark D. Zoback, Herb Wang, Kate Condon, Ahmad Ghassemi, Hao Chen, Mark W. McClure, George Vandine, Douglas Blankenship, Timothy J. Kneafsey
Summary: This study analyzed data from hydraulic fracturing tests in an underground testbed to determine the characteristics and development process of fractures. It was found that hydraulic fractures could cross natural fractures and continue to propagate under continued stimulation, while mineral-filled natural fractures did not have a significant impact on hydraulic fracture propagation. The high-quality data sets allowed confident conclusions to be drawn, highlighting the advantages of intermediate-scale experiments in subsurface research.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2021)
Article
Energy & Fuels
Hui Wu, Pengcheng Fu, Zachary Frone, Mark D. White, Jonathan B. Ajo-Franklin, Joseph P. Morris, Hunter A. Knox, Paul C. Schwering, Christopher E. Strickland, Benjamin Q. Roberts, Vince R. Vermeul, Earl D. Mattson, Mathew D. Ingraham, Timothy J. Kneafsey, Douglas A. Blankenship
Summary: The study analyzed the heat transport processes in an intermediate-scale EGS field experiment, and validated the effectiveness of numerical simulations in modeling heat recovery processes through high-fidelity models and numerical approaches.
Article
Green & Sustainable Science & Technology
Hewei Tang, Pengcheng Fu, Christopher S. Sherman, Jize Zhang, Xin Ju, Francois Hamon, Nicholas A. Azzolina, Matthew Burton-Kelly, Joseph P. Morris
Summary: Updating pressure buildup and CO2 plume migration forecasts quickly in geologic carbon storage faces challenges. A workflow combining physical understandings with deep learning techniques can achieve history matching and reservoir forecasting with uncertainty quantification in less than an hour. By leveraging surrogate models and advanced neural networks, this workflow provides a fast and accurate solution for reservoir management.
INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL
(2021)
Article
Geochemistry & Geophysics
Honggeun Jo, Yongchae Cho, Michael Pyrcz, Hewei Tang, Pengcheng Fu
Summary: Estimating porosity models from seismic data is challenging due to low signal-to-noise ratio and insufficient resolution. In this paper, a machine learning-based workflow is proposed to convert seismic data into porosity models. The workflow uses a residual U-Net++ architecture to estimate porosity models from multiple poststack seismic volumes. Experimental results show that the method achieves high accuracy and robustness in porosity estimation, but further research and improvements are needed.
Article
Green & Sustainable Science & Technology
Hewei Tang, Pengcheng Fu, Honggeun Jo, Su Jiang, Christopher S. Sherman, Francois Hamon, Nicholas A. Azzolina, Joseph P. Morris
Summary: This study presents a fast forecasting method for the reservoir pressure distribution in geologic carbon storage (GCS) using low-cost InSAR data and a deep learning-accelerated workflow. By assimilating surface displacement maps and predicting dynamic reservoir pressure, the method is able to complete data assimilation and pressure forecasting in half an hour.
INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL
(2022)
Article
Meteorology & Atmospheric Sciences
D. L. McGuffin, D. D. Lucas, J. P. Morris, G. D. Spriggs, K. B. Knight
Summary: Nuclear detonations produce hazardous particles that can fall out and deposit locally or globally. Accurately predicting the size and distribution of these fallout particles is crucial for assessing the extent of radiation hazard. This study applies a cloud precipitation modeling technique to simulate the size distribution of particles in mushroom clouds formed after nuclear detonations. The simulation results are validated against historical test measurements, and different detonation scenarios are explored to predict particle sizes.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2022)
Article
Engineering, Petroleum
Wei Fu, Joseph Morris, Pengcheng Fu, Jixiang Huang, Christopher Sherman, Randolph Settgast, Hui Wu, Frederick Ryerson
Summary: This study aims to address the challenge of tightly spaced hydraulic fractures observed in core samples from the hydraulic fracturing test site in the Middle Wolfcamp Formation. The research develops a numerical approach to effectively simulate densely spaced hydraulic fractures and presents an upscaling law to predict reservoir response to fracture swarms. The results show that accounting for fracture swarming in field-scale simulations can significantly affect fracture propagation behaviors and improve the accuracy of reservoir response predictions.
