Download or read book Hydraulic Fracturing in Naturally Fractured Reservoirs and the Impact of Geomechanics on Microseismicity written by Himanshu Yadav and published by . This book was released on 2011 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic fracturing in tight gas and shale gas reservoirs is an essential stimulation technique for production enhancement. Often, hydraulic fracturing induces fracture patterns that are more complex than the planar geometry that has been assumed in the past models. These complex patterns arise as a result of the presence of planes of weakness, faults and/or natural fractures. In this thesis, two different 3D geomechanical models have been developed to simulate the interaction between the hydraulic fracture and the natural fractures, and to observe the impact of geomechanics on the potential microseismicity in these naturally fractured formations. Several cases were studied to observe the effects of natural fracture geometry, fracturing treatment, mechanical properties of the sealed fractures, etc. on the propagation path of the hydraulic fracture in these formations, and were found to be consistent with past experimental results. Moreover, the effects of several parameters including cohesiveness of the sealed natural fractures, mechanical properties of the formation, treatment parameters, etc. have been studied from the potential microseismicity standpoint. It is shown that the impact of geomechanics on potential microseismicity is significant and can influence the desired fracture spacing. In this thesis, the presented model quantifies the extent of potential microseismic volume (MSV) resulting from hydraulic fracturing in unconventional reservoirs. The model accounts for random geometries of the weak planes (with different dip and strike) observed in the field. The work presented here shows, for the first time, a fracture treatment can be designed to maximize the MSV, when the fractures form a complicated network of fractures, and in turn influence the desired fracture spacing in horizontal wells. Our work shows that by adjusting the fluid rheology and other treatment parameters, the spatial extent of MSV and the desired fracture spacing can be optimized for a given set of shale properties.

Download or read book Microseismic Imaging of Hydraulic Fracturing written by Shawn Mawell and published by SEG Books. This book was released on 2014-01-01 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microseismic Imaging of Hydraulic Fracturing: Improved Engineering of Unconventional Shale Reservoirs (SEG Distinguished Instructor Series No. 17) covers the use of microseismic data to enhance engineering design of hydraulic fracturing and well completion. The book, which accompanies the 2014 SEG Distinguished Instructor Short Course, describes the design, acquisition, processing, and interpretation of an effective microseismic project. The text includes a tutorial of the basics of hydraulic fracturing, including the geologic and geomechanical factors that control fracture growth. In addition to practical issues associated with collecting and interpreting microseismic data, potential pitfalls and quality-control steps are discussed. Actual case studies are used to demonstrate engineering benefits and improved production through the use of microseismic monitoring. Providing a practical user guide for survey design, quality control, interpretation, and application of microseismic hydraulic fracture monitoring, this book will be of interest to geoscientists and engineers involved in development of unconventional reservoirs.

Download or read book Geomechanics and Hydraulic Fracturing for Shale Reservoirs written by Yu Wang and published by Scientific Research Publishing, Inc. USA. This book was released on 2020-07-01 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is intended as a reference book for advanced graduate students and research engineers in shale gas development or rock mechanical engineering. Globally, there is widespread interest in exploiting shale gas resources to meet rising energy demands, maintain energy security and stability in supply and reduce dependence on higher carbon sources of energy, namely coal and oil. However, extracting shale gas is a resource intensive process and is dependent on the geological and geomechanical characteristics of the source rocks, making the development of certain formations uneconomic using current technologies. Therefore, evaluation of the physical and mechanical properties of shale, together with technological advancements, is critical in verifying the economic viability of such formation. Accurate geomechanical information about the rock and its variation through the shale is important since stresses along the wellbore can control fracture initiation and frac development. In addition, hydraulic fracturing has been widely employed to enhance the production of oil and gas from underground reservoirs. Hydraulic fracturing is a complex operation in which the fluid is pumped at a high pressure into a selected section of the wellbore. The interaction between the hydraulic fractures and natural fractures is the key to fracturing effectiveness prediction and high gas development. The development and growth of a hydraulic fracture through the natural fracture systems of shale is probably more complex than can be described here, but may be somewhat predictable if the fracture system and the development of stresses can be explained. As a result, comprehensive shale geomechanical experiments, physical modeling experiment and numerical investigations should be conducted to reveal the fracturing mechanical behaviors of shale.

Download or read book Geomechanical Studies of the Barnett Shale Texas USA written by John Peter Vermylen and published by Stanford University. This book was released on 2011 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents five studies of a gas shale reservoir using diverse methodologies to investigate geomechanical and transport properties that are important across the full reservoir lifecycle. Using the Barnett shale as a case study, we investigated adsorption, permeability, geomechanics, microseismicity, and stress evolution in two different study areas. The main goals of this thesis can be divided into two parts: first, to investigate how flow properties evolve with changes in stress and gas species, and second, to understand how the interactions between stress, fractures, and microseismicity control the creation of a permeable reservoir volume during hydraulic fracturing. In Chapter 2, we present results from adsorption and permeability experiments conducted on Barnett shale rock samples. We found Langmuir-type adsorption of CH4 and N2 at magnitudes consistent with previous studies of the Barnett shale. Three of our samples demonstrated BET-type adsorption of CO2, in contrast to all previous studies on CO2 adsorption in gas shales, which found Langmuir-adsorption. At low pressures (600 psi), we found preferential adsorption of CO2 over CH4 ranging from 3.6x to 5.5x. While our measurements were conducted at low pressures (up to 1500 psi), when our model fits are extrapolated to reservoir pressures they reach similar adsorption magnitudes as have been found in previous studies. At these high reservoir pressures, the very large preferential adsorption of CO2 over CH4 (up to 5-10x) suggests a significant potential for CO2 storage in gas shales like the Barnett if practical problems of injectivity and matrix transport can be overcome. We successfully measured permeability versus effective stress on two intact Barnett shale samples. We measured permeability effective stress coefficients less than 1 on both samples, invalidating our hypothesis that there might be throughgoing flow paths within the soft, porous organic kerogen that would lead the permeability effective stress coefficient to be greater than 1. The results suggest that microcracks are likely the dominant flow paths at these scales. In Chapter 3, we present integrated geological, geophysical, and geomechanical data in order to characterize the rock properties in our Barnett shale study area and to model the stress state in the reservoir before hydraulic fracturing occurred. Five parallel, horizontal wells were drilled in the study area and then fractured using three different techniques. We used the well logs from a vertical pilot well and a horizontal well to constrain the stress state in the reservoir. While there was some variation along the length of the well, we were able to determine a best fit stress state of Pp = 0.48 psi/ft, Sv = 1.1 psi/ft, SHmax = 0.73 psi/ft, and Shmin = 0.68 psi/ft. Applying this stress state to the mapped natural fractures indicates that there is significant potential for induced shear slip on natural fracture planes in this region of the Barnett, particularly close to the main hydraulic fracture where the pore pressure increase during hydraulic fracturing is likely to be very high. In Chapter 4, we present new techniques to quantify the robustness of hydraulic fracturing in gas shale reservoirs. The case study we analyzed involves five parallel horizontal wells in the Barnett shale with 51 frac stages. To investigate the numbers, sizes, and types of microearthquakes initiated during each frac stage, we created Gutenberg-Richter-type magnitude distribution plots to see if the size of events follows the characteristic scaling relationship found in natural earthquakes. We found that slickwater fracturing does generate a log-linear distribution of microearthquakes, but that it creates proportionally more small events than natural earthquake sources. Finding considerable variability in the generation of microearthquakes, we used the magnitude analysis as a proxy for the "robustness" of the stimulation of a given stage. We found that the conventionally fractured well and the two alternately fractured wells ("zipperfracs") were more effective than the simultaneously fractured wells ("simulfracs") in generating microearthquakes. We also found that the later stages of fracturing a given well were more successful in generating microearthquakes than the early stages. In Chapter 5, we present estimates of stress evolution in our study reservoir through analysis of the instantaneous shut-in pressure (ISIP) at the end of each stage. The ISIP increased stage by stage for all wells, but the simulfrac wells showed the greatest increase and the zipperfrac wells the least. We modeled the stress increase in the reservoir with a simple sequence of 2-D cracks along the length of the well. When using a spacing of one crack per stage, the modeled stress increase was nearly identical to the measured stress increase in the zipperfrac wells. When using three cracks per stage, the modeled final stage stress magnitude matched the measured final stage stress magnitude from the simulfrac wells, but the rate of stress increase in the simulfrac wells was much more gradual than the model predicted. To further investigate the causes of these ISIP trends, we began numerical flow and stress analysis to more realistically model the processes in the reservoir. One of our hypotheses was that the shorter total time needed to complete all the stages of the simulfrac wells was the cause of the greater ISIP increase compared to the zipperfrac wells. The microseismic activity level measured in Chapter 4 also correlates with total length of injection, suggesting leak off into the reservoir encouraged shear failure. Numerical modeling using the coupled FEM and flow software GEOSIM was able to model some cumulative stress increase the reservoir, but the full trend was not replicated. Further work to model field observations of hydraulic fracturing will enhance our understanding of the impact that hydraulic fracturing and stress change have on fracture creation and permeability enhancement in gas shales.

Download or read book An Integrated Geomechanics and Petrophysics Study of Hydraulic Fracturing in Naturally Fractured Reservoirs written by Xiaochun Jin and published by . This book was released on 2014 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unconventional Reservoir Geomechanics written by Mark D. Zoback and published by Cambridge University Press. This book was released on 2019-05-16 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive overview of the key geologic, geomechanical and engineering principles that govern the development of unconventional oil and gas reservoirs. Covering hydrocarbon-bearing formations, horizontal drilling, reservoir seismology and environmental impacts, this is an invaluable resource for geologists, geophysicists and reservoir engineers.

Download or read book Imaging the Mechanics of Hydraulic Fracturing in Naturally fractured Reservoirs Using Induced Seismicity and Numerical Modeling written by Xueping Zhao and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Simulation and Production Evaluation of Multiple stage Hydraulic Fracturing in Horizontal Wellbores written by Mahdi Haddad and published by . This book was released on 2017 with total page 1150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shale formations have globally emerged as the sustainable hydrocarbon resources in the advent of the technologies for the economic production from these formations: horizontal drilling combined with multiple-stage hydraulic fracturing. The viable production from these resources requires a maximized stimulated reservoir volume encompassing a complex induced fracture network, which is highly dependent on the stimulation design. The optimization of the ultimate recovery requires integrated fracturing models with reservoir models in virtue of the limitations on the field data acquisition and their reliability, the high-cost of re-stimulation plans, and low-fidelity current reservoir simulation workflows. We proposed 2D and 3D hydraulic-fracturing models on the basis of the cohesive zone model (CZM) and extended finite element method (XFEM) with a combination of the following capabilities: (1) inclusion of fracture intersections via pore-pressure coupling; (2) fully-coupled poroelasticity in matrix, continuum-based leakoff, and slit flow in fracture(s) with the cohesive behavior for fracture growth. These models were validated in comparison with KGD solution, and were employed for the hydraulic-fracturing design and understanding microseismic event distributions. Moreover, the output of these models in a specific 2D case was integrated with a reservoir simulation workflow for the prediction of long-term production from the induced fracture network. Our 2D and 3D fracture-intersection cases demonstrate the significant role of the following parameters in the growth pattern of fractures upon intersection: (1) the length of the initially open segment of the natural fracture at the intersection; (2) the horizontal stress contrast; (3) the distance between the injection point and the intersection. Notably, hydraulic fracturing in higher depths with higher horizontal stress contrasts and closer injection points to the intersection causes more extensive natural-fracture opening and shear slippage. Also, we demonstrated the application of the proposed 3D fracture intersection model for further understanding of the anomalies observed in the Vaca Muerta Shale. This study revealed that the microseismic events at shallower depths, later times, and deviated from the expected planar distribution are mainly associated with shear slippage along weak interfaces due to the induced stresses by hydraulic fracturing. Thereby, our explicit modeling of fluid infiltration into the natural fracture(s) at the intersection leads to better understanding of the nature of microseismic events. Our multiple-stage, multiple-wellbore, hydraulic-fracturing model for naturally fractured reservoirs includes the operational and field components during the shale stimulations such as perforation tunnel length distribution, horizontal wellbores, stochastically-retrieved fully-cemented natural-fracture network, plugs for the stage stimulation (via connector elements), and external stimulation scenarios (controlled by programming the connector elements in an external user subroutine). The application of this model on synthetic cases shows the following: (1) sequential fracturing with limited number of clusters per stage leads to more control on the cluster stimulation in the presence of the non-uniform perforation tunnel length distribution and wellbore model; (2) proportional cluster efficiency with the perforation tunnel length (promoting the consistent perforation technology); (3) over-estimation of the cluster stimulation in the absence of the wellbore model and/or the natural-fracture network; and (4) more-viscous fracturing fluids conclude less complex induced fracture network (in agreement with the common field observations). The initial natural-fracture network in this model was retrieved from the proposed object-based method. Also, the transfer of the induced fracture network into an embedded discrete fracture model is featured by the higher fidelity in the estimation of long-term gas production from naturally fractured reservoirs. For the investigation of the effect of in-situ stresses on the reservoir engineering problems, we implemented the coupling of a geomechanics module with the UTCOMP reservoir simulator. We first validated this implementation via comparing the results with GPAS and CMG results at various cases. Our improvements in the geomechanics module (lowering the frequency of calling the geomechanics module and the order of the finite-element shape functions) significantly reduced the computational expenses while maintaining the solution accuracy. Overall, water flooding shows more sensitivity to the number of the reservoir-simulation time steps per geomechanics call than gas flooding cases (e.g., CO2 injection). Our reservoir simulation model for re-fracturing included various injection and production steps to show the effect of the re-fracturing fluid injection in a depleted formation on the ultimate recovery. This study showed the significant effect of the re-fracturing water injection in production via changing a single-phase to two-phase gas flow regime and deeper water invasion into the matrix due to the pressure depletion (after primary production)

Download or read book Microseismic Monitoring written by Vladimir Grechka and published by SEG Books. This book was released on 2017-09-01 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, microseismic monitoring, a technology developed for evaluating completions of wells drilled to produce hydrocarbons from unconventional reservoirs, has grown increasingly popular among oil and gas companies. Microseismic Monitoring, by Vladimir Grechka and Werner M. Heigl, discusses how to process microseismic data, what can and cannot be inferred from such data, and to what level of certainty this might be possible. The narrative of the book follows the passage of seismic waves: from a source triggered by hydraulic fracture stimulation, through hydrocarbon-bearing formations, towards motion sensors. The waves’ characteristics encode the location of their source and its focal mechanism. The analysis of various approaches to harvesting the source-related information from microseismic records has singled out the accuracy of the velocity model, fully accounting for the strong elastic anisotropy of hydraulically fractured shales, as the most critical ingredient for obtaining precise source locations and interpretable moment tensors. The ray theory complemented by its modern extensions, paraxial and Fréchet ray tracing, provides the only practical means available today for building such models. The book is written for geophysicists interested in learning and applying advanced microseismic data-processing techniques.

Download or read book Exploitation of Unconventional Oil and Gas Resources written by Kenneth Imo-Imo Israel Eshiet and published by . This book was released on 2019-07-10 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stimulation of unconventional hydrocarbon reservoirs is proven to improve their productivity to an extent that has rendered them economically viable. Generally, the stimulation design is a complex process dependent on intertwining factors such as the history of the formation, rock and reservoir fluid type, lithology and structural layout of the formation, cost, time, etc. A holistic grasp of these can be daunting, especially for people without sufficient experience and/or expertise in the exploitation of unconventional hydrocarbon reserves. This book presents the key facets integral to producing unconventional resources, and how the different components, if pieced together, can be used to create an integrated stimulation design. Areas covered are as follows: • stimulation methods, • fracturing fluids, • mixing and behavior of reservoir fluids, • assessment of reservoir performance, • integration of surface drilling data, • estimation of geomechanical properties and hydrocarbon saturation, and • health and safety. Exploitation of Unconventional Oil and Gas Resources: Hydraulic Fracturing and Other Recovery and Assessment Techniques is an excellent introduction to the subject area of unconventional oil and gas reservoirs, but it also complements existing information in the same discipline. It is an essential text for higher education students and professionals in academia, research, and the industry.

Download or read book Mechanics of Hydraulic Fracturing written by Xin-rong Zhang and published by John Wiley & Sons. This book was released on 2023-01-05 with total page 291 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanics of Hydraulic Fracturing Comprehensive single-volume reference work providing an overview of experimental results and predictive methods for hydraulic fracture growth in rocks Mechanics of Hydraulic Fracturing: Experiment, Model, and Monitoring provides a summary of the research in mechanics of hydraulic fractures during the past two decades, plus new research trends to look for in the future. The book covers the contributions from theory, modeling, and experimentation, including the application of models to reservoir stimulation, mining preconditioning, and the formation of geological structures. The four expert editors emphasize the variety of diverse methods and tools in hydraulic fracturing and help the reader understand hydraulic fracture mechanics in complex geological situations. To aid in reader comprehension, practical examples of new approaches and methods are presented throughout the book. Key topics covered in the book include: Prediction of fracture shapes, sizes, and distributions in sedimentary basins, plus their importance in petroleum industry Real-time monitoring methods, such as micro-seismicity and trace tracking How to uncover geometries of fractures like dikes and veins Fracture growth of individual foundations and its applications Researchers and professionals working in the field of fluid-driven fracture growth will find immense value in this comprehensive reference on hydraulic fracturing mechanics.

Download or read book Optimization of Hydraulic Fracture Stages and Sequencing in Unconventional Formations written by Ahmed Alzahabi and published by CRC Press. This book was released on 2018-07-03 with total page 279 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shale gas and/or oil play identification is subject to many screening processes for characteristics such as porosity, permeability, and brittleness. Evaluating shale gas and/or oil reservoirs and identifying potential sweet spots (portions of the reservoir rock that have high-quality kerogen content and brittle rock) requires taking into consideration multiple rock, reservoir, and geological parameters that govern production. The early determination of sweet spots for well site selection and fracturing in shale reservoirs is a challenge for many operators. With this limitation in mind, Optimization of Hydraulic Fracture Stages and Sequencing in Unconventional Formations develops an approach to improve the industry’s ability to evaluate shale gas and oil plays and is structured to lead the reader from general shale oil and gas characteristics to detailed sweet-spot classifications. The approach uses a new candidate selection and evaluation algorithm and screening criteria based on key geomechanical, petrophysical, and geochemical parameters and indices to obtain results consistent with existing shale plays and gain insights on the best development strategies going forward. The work introduces new criteria that accurately guide the development process in unconventional reservoirs in addition to reducing uncertainty and cost.

Download or read book Applied Concepts in Fractured Reservoirs written by John C. Lorenz and published by John Wiley & Sons. This book was released on 2020-01-13 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt: A much-needed, precise and practical treatment of a key topic in the energy industry and beyond, Applied Concepts in Fractured Reservoirs is an invaluable reference for those in both industry and academia Authored by renowned experts in the field, this book covers the understanding, evaluation, and effects of fractures in reservoirs. It offers a comprehensive yet practical discussion and description of natural fractures, their origins, characteristics, and effects on hydrocarbon reservoirs. It starts by introducing the reader to basic definitions and classifications of fractures and fractured reservoirs. It then provides an outline for fractured-reservoir characterization and analysis, and goes on to introduce the way fractures impact operational activities. Well organized and clearly illustrated throughout, Applied Concepts in Fractured Reservoirs starts with a section on understanding natural fractures. It looks at the different types, their dimensions, and the mechanics of fracturing rock in extension and shear. The next section provides information on measuring and analyzing fractures in reservoirs. It covers: logging core for fractures; taking, measuring, and analyzing fracture data; new core vs. archived core; CT scans; comparing fracture data from outcrops, core, and logs; and more. The last part examines the effects of natural fractures on reservoirs, including: the permeability behavior of individual fractures and fracture systems; fracture volumetrics; effects of fractures on drilling and coring; and the interaction between natural and hydraulic fractures. Teaches readers to understand and evaluate fractures Compiles and synthesizes various concepts and descriptions scattered in literature and synthesizes them with unpublished oil-field observations and data, along with the authors’ own experience Bridges some of the gaps between reservoir engineers and geologists Provides an invaluable reference for geologists and engineers who need to understand naturally fractured reservoirs in order to efficiently extract hydrocarbons Illustrated in full color throughout Companion volume to the Atlas of Natural and Induced Fractures in Core

Download or read book Geologic Analysis of Naturally Fractured Reservoirs written by Ronald Nelson and published by Elsevier. This book was released on 2001-08-24 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geologists, engineers, and petrophysicists concerned with hydrocarbon production from naturally fractured reservoirs will find this book a valuable tool for obtaining pertinent rock data to evaluate reserves and optimize well location and performance. Nelson emphasizes geological, petrophysical, and rock mechanics to complement other studies of the subject that use well logging and classical engineering approaches. This well organized, updated edition contains a wealth of field and laboratory data, case histories, and practical advice. A great how-to-guide for anyone working with fractured or highly anisotropic reservoirs Provides real-life illustrations through case histories and field and laboratory data

Download or read book Numerical Simulation in Hydraulic Fracturing Multiphysics Theory and Applications written by Xinpu Shen and published by CRC Press. This book was released on 2017-03-27 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: The expansion of unconventional petroleum resources in the recent decade and the rapid development of computational technology have provided the opportunity to develop and apply 3D numerical modeling technology to simulate the hydraulic fracturing of shale and tight sand formations. This book presents 3D numerical modeling technologies for hydraulic fracturing developed in recent years, and introduces solutions to various 3D geomechanical problems related to hydraulic fracturing. In the solution processes of the case studies included in the book, fully coupled multi-physics modeling has been adopted, along with innovative computational techniques, such as submodeling. In practice, hydraulic fracturing is an essential project component in shale gas/oil development and tight sand oil, and provides an essential measure in the process of drilling cuttings reinjection (CRI). It is also an essential measure for widened mud weight window (MWW) when drilling through naturally fractured formations; the process of hydraulic plugging is a typical application of hydraulic fracturing. 3D modeling and numerical analysis of hydraulic fracturing is essential for the successful development of tight oil/gas formations: it provides accurate solutions for optimized stage intervals in a multistage fracking job. It also provides optimized well-spacing for the design of zipper-frac wells. Numerical estimation of casing integrity under stimulation injection in the hydraulic fracturing process is one of major concerns in the successful development of unconventional resources. This topic is also investigated numerically in this book. Numerical solutions to several other typical geomechanics problems related to hydraulic fracturing, such as fluid migration caused by fault reactivation and seismic activities, are also presented. This book can be used as a reference textbook to petroleum, geotechnical and geothermal engineers, to senior undergraduate, graduate and postgraduate students, and to geologists, hydrogeologists, geophysicists and applied mathematicians working in this field. This book is also a synthetic compendium of both the fundamentals and some of the most advanced aspects of hydraulic fracturing technology.

Download or read book Coupled Flow and Geomechanics Modeling for Fractured Poroelastic Reservoirs written by Gurpreet Singh and published by . This book was released on 2014 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tight gas and shale oil play an important role in energy security and in meeting an increasing energy demand. Hydraulic fracturing is a widely used technology for recovering these resources. The design and evaluation of hydraulic fracture operation is critical for efficient production from tight gas and shale plays. The efficiency of fracturing jobs depends on the interaction between hydraulic (induced) and naturally occurring discrete fractures. In this work, a coupled reservoir-fracture flow model is described which accounts for varying reservoir geometries and complexities including non-planar fractures. Different flow models such as Darcy flow and Reynold's lubrication equation for fractures and reservoir, respectively are utilized to capture flow physics accurately. Furthermore, the geomechanics effects have been included by considering a multiphase Biot's model. An accurate modeling of solid deformations necessitates a better estimation of fluid pressure inside the fracture. The fractures and reservoir are modeled explicitly allowing accurate representation of contrasting physical descriptions associated with each of the two. The approach presented here is in contrast with existing averaging approaches such as dual and discrete-dual porosity models where the effects of fractures are averaged out. A fracture connected to an injection well shows significant width variations as compared to natural fractures where these changes are negligible. The capillary pressure contrast between the fracture and the reservoir is accounted for by utilizing different capillary pressure curves for the two features. Additionally, a quantitative assessment of hydraulic fracturing jobs relies upon accurate predictions of fracture growth during slick water injection for single and multistage fracturing scenarios. It is also important to consistently model the underlying physical processes from hydraulic fracturing to long-term production. A recently introduced thermodynamically consistent phase-field approach for pressurized fractures in porous medium is utilized which captures several characteristic features of crack propagation such as joining, branching and non-planar propagation in heterogeneous porous media. The phase-field approach captures both the fracture-width evolution and the fracture-length propagation. In this work, the phase-field fracture propagation model is briefly discussed followed by a technique for coupling this to a fractured poroelastic reservoir simulator. We also present a general compositional formulation using multipoint flux mixed finite element (MFMFE) method on general hexahedral grids with a future prospect of treating energized fractures. The mixed finite element framework allows for local mass conservation, accurate flux approximation and a more general treatment of boundary conditions. The multipoint flux inherent in MFMFE scheme allows the usage of a full permeability tensor. An accurate treatment of diffusive/dispersive fluxes owing to additional velocity degrees of freedom is also presented. The applications areas of interest include gas flooding, CO2 sequestration, contaminant removal and groundwater remediation.

Download or read book Hydraulic Fracture Modeling written by Yu-Shu Wu and published by Gulf Professional Publishing. This book was released on 2017-11-30 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic Fracture Modeling delivers all the pertinent technology and solutions in one product to become the go-to source for petroleum and reservoir engineers. Providing tools and approaches, this multi-contributed reference presents current and upcoming developments for modeling rock fracturing including their limitations and problem-solving applications. Fractures are common in oil and gas reservoir formations, and with the ongoing increase in development of unconventional reservoirs, more petroleum engineers today need to know the latest technology surrounding hydraulic fracturing technology such as fracture rock modeling. There is tremendous research in the area but not all located in one place. Covering two types of modeling technologies, various effective fracturing approaches and model applications for fracturing, the book equips today’s petroleum engineer with an all-inclusive product to characterize and optimize today’s more complex reservoirs. Offers understanding of the details surrounding fracturing and fracture modeling technology, including theories and quantitative methods Provides academic and practical perspective from multiple contributors at the forefront of hydraulic fracturing and rock mechanics Provides today’s petroleum engineer with model validation tools backed by real-world case studies