Jennifer Miskimins, Editor-in-Chief
2019
Softcover
ISBN: 978-1-61399-719-2
Society of Petroleum Engineers

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With an author team of 26 subject-matter experts representing a diversity of talent, background, and experience, Hydraulic Fracturing:  Fundamentals and Advancements delivers a comprehensive discussion on the principles of hydraulic fracturing while also including the latest processes that have prompted the explosive growth in stimulating horizontal wells in shale and tight oil and gas reservoirs.

Brief Table of Contents
Chapter 1 Overview
Chapter 2 Pretreatment Formation Evaluation
Chapter 3 Rock Mechanics and Fracture Geometry
Chapter 4 Hydraulic Fracture Modeling
Chapter 5 Proppants and Fracture Conductivity
Chapter 6 Fracturing Fluids and Additives
Chapter 7 Fluid Leakoff
Chapter 8 Flow Behavior of Fracturing Fluids
Chapter 9 Proppant Transport
Chapter 10 Hydraulic Fracturing Treatment Design
Chapter 11 Well Completions
Chapter 12 Field Implementation of Hydraulic Fracturing
Chapter 13 Fracturing Pressure Analysis
Chapter 14 Flowback and Early-Time Production Data Analysis
Chapter 15 Fracture Diagnostics
Chapter 16 Economics of Fracturing
Chapter 17 Acid Fracturing
Chapter 18 Refracturing

 

CHAPTER 1  OVERVIEW
George E. King, Jennifer L. Miskimins

George E. King is a registered professional engineer with 47 years of oilfield experience, having started his career with Amoco in 1971. He currently consults on well completions, interventions, and well failures, working through Viking Engineering. King holds a BS degree in chemistry from Oklahoma State University and BS and MS degrees in chemical engineering and petroleum engineering, respectively, from the University of Tulsa.

Jennifer L. Miskimins is the interim department head and an associate professor in the Petroleum Engineering Department at the Colorado School of Mines. Her research interests focus on the areas of hydraulic fracturing, stimulation, completions, and unconventional reservoirs.  Miskimins holds a BS degree in petroleum engineering from the Montana College of Mineral Science and Technology and MS and PhD degrees in petroleum engineering from the Colorado School of Mines. She is an active member of SPE.


CHAPTER 2  PRETREATMENT FORMATION EVALUATION

John McLennan, Larry Britt, Siavash Nadami

John McLennan
 is a USTAR associate professor in the Department of Chemical Engineering at the University of Utah. He has more than 35 years of experience in the petroleum service and technology sectors, working on projects concerned with subsurface energy recovery (hydrocarbon and geothermal). McLennan holds a PhD degree in civil engineering from the University of Toronto.

Larry K. Britt is a partner with NSI Fracturing and owns and operates Britt Rock Mechanics Laboratory at the University of Tulsa. He also serves as an adjunct professor at the Missouri University of Science and Technology. Britt holds a BS degree in geological engineering and a professional degree in petroleum engineering, both from the Missouri University of Science and Technology. He is an SPE Distinguished Member.

Siavash Nadimi
is an associate oil and gas engineer with the California Division of Oil, Gas, and Geothermal Resources. He has more than 7 years of experience in reservoir engineering and geomechanics with petroleum service and technology companies. Nadimi holds an MS degree in rock mechanics from Amirkabir University of Technology, as well as an MS degree in mining engineering and a PhD in chemical engineering from the University of Utah.


CHAPTER 3  ROCK MECHANICS AND FRACTURE GEOMETRY

Norm Warpinski

Norm R. Warpinski served as a Technology Fellow at Halliburton in Houston, Texas, where he oversaw the development of new tools and analyses for hydraulic fracture mapping, reservoir monitoring, hydraulic fracture design and analysis, and integrated monitoring solutions for reservoir development. He retired from the company in July 2016. Warpinski holds a BS degree in mechanical engineering from Illinois Institute of Technology and MS and PhD degrees in mechanical engineering from the University of Illinois, Champaign/Urbana.


CHAPTER 4  HYDRAULIC FRACTURE MODELING

Leen Weijers, Hans de Pater

Leen Weijers is the vice-president of engineering at Liberty Oilfield Services LLC. He has played a key role in the calibration of fracture-growth models using various fracture diagnostics such as tiltmeter and microseismic-fracture-mapping technologies. Weijers holds a doctorate from the Faculty of Mining and Petroleum Engineering at Delft University of Technology in the Netherlands.

Hans de Pater is a partner, consultant, and general manager of Fenix Consulting Delft, working primarily on rock-mechanics-related projects and fully coupled rock-mechanical reservoir simulation. He holds a PhD degree in applied physics from Delft University of Technology.


CHAPTER 5  PROPPANTS AND FRACTURE CONDUCTIVITY

David Milton-Taylor, Robert Duenckel

David Milton-Taylor is the technology manager at FracTech Limited, a private firm that offers technology services to the oil and gas
industry in the UK and internationally.

Robert Duenckel
is vice president in the Stim-Lab Division of CoreLab. His interests are directed at all aspects of hydraulic fracturing.  Duenckel is a registered professional engineer and holds a BS degree in petroleum engineering from Missouri University of Science and Technology.


CHAPTER 6  FRACTURING FLUIDS AND ADDITIVES

John Ely, Ray Herndon

John W. Ely is the founder and chief operating office of Ely and Associates, Inc. He has more than 50 years of experience in the oil and gas industry, having started his career with Halliburton in 1965. Ely holds a BS degree in chemistry from Oklahoma State University. He is a member of SPE and the American Chemical Society, and is a fellow of the American Institute of Chemistry.

Raymond A. Herndon is a fracturing consultant, currently working with Ely and Associates, Inc. He has more than 30 years of experience in fracturing stimulation, having started his career with Halliburton in 1980. Herndon holds a BS degree in engineering from the University of Texas at Austin.


CHAPTER 7  FLUID LEAKOFF

Ghaithan Muntasheri, Msalli Otaibi

Ghaithan A. Al-Muntasheri is the chief technologist of the Production Technology Team in the EXPEC Advanced Research Center of Saudi Aramco in Dhahran, Saudi Arabia. He holds bachelor’s and master’s degrees in chemical engineering from King Fahd University of Petroleum and Minerals, Saudi Arabia, and a PhD degree in petroleum engineering from Delft University of Technology. Al-Muntasheri is an SPE Distinguished Member.

Msalli A. Al-Otaibi is the drilling fluid and cementing unit supervisor with the EXPEC Advanced Research Center of Saudi Aramco. His interests include hydraulic fracturing, proppant transport in complex fractures, and drilling fluids. Al-Otaibi holds a BS degree in chemical engineering from Louisiana State University, an MS degree in chemical engineering from King Fahd University of Petroleum and Minerals, and a PhD degree in petroleum engineering from Colorado School of Mines.


CHAPTER 8  FLOW BEHAVIOR OF FRACTURING FLUIDS

Subhash Shah

Subhash N. Shah is Emeritus Professor in the School of Petroleum and Geological Engineering at the University of Oklahoma. He is also Shell Total Chair Professor in the School of Petroleum Technology at Pandit Deendayal Petroleum University, Gandhinagar, India. His research interests include drilling and well completions, stimulation, coiled-tubing applications, and non-Newtonian fluids characterization. Shah holds a BE degree in chemical engineering from University of Baroda, India, and MS and PhD degrees in chemical engineering from University of New Mexico. He is an SPE Lifetime Member and a Fellow of the American Institute of Chemical Engineers.


CHAPTER 9  PROPPANT TRANSPORT

Subhash Shah, Harsh Patel

Subhash N. Shah is Emeritus Professor in the School of Petroleum and Geological Engineering at the University of Oklahoma. He is also Shell Total Chair Professor in the School of Petroleum Technology at Pandit Deendayal Petroleum University, Gandhinagar, India. His research interests include drilling and well completions, stimulation, coiled-tubing applications, and non-Newtonian fluids characterization. Shah holds a BE degree in chemical engineering from University of Baroda, India, and MS and PhD degrees in chemical engineering from University of New Mexico. He is an SPE Lifetime Member and a Fellow of the American Institute of Chemical Engineers.

Harsh R. Patel is a PhD candidate in the School of Petroleum and Geological Engineering at the University of Oklahoma. His research interests include drilling and well completions, well integrity and barriers, stimulation, and non-Newtonian fluids characterization. Patel holds BTech and MS degrees in petroleum engineering from Pandit Deendayal Petroleum University, India, and the University of Oklahoma, respectively.


CHAPTER 10  HYDRAULIC FRACTURING TREATMENT DESIGN

Vibhas Pandey, David Cramer

Vibhas J. Pandey is an engineering fellow in the Global Completions Engineering Group at ConocoPhillips in Houston, Texas. He has more than 30 years of industry experience and has held lead positions in several disciplines, including drilling, workovers, well stimulation, and product development. Pandey holds BE and ME degrees in mechanical engineering from the National Institute of Technology in Surat, India, and an MS degree in petroleum engineering from the University of Oklahoma.

David D. Cramer is a senior engineering fellow in the Global Completions Engineering Group at ConocoPhillips in Houston, Texas, and a registered professional engineer in the state of Colorado. He has more than 40 years of experience in designing, implementing, and evaluating well-stimulation treatments. Cramer holds a bachelor’s degree from Rutgers University in New Brunswick, New Jersey.


CHAPTER 11  WELL COMPLETIONS

Ernie Brown, Chris Fredd

Ernie Brown worked for Schlumberger for 36 years before retiring and now serves as their consulting technical advisor. During his time at Schlumberger he worked at several international locations in various technical positions related to reservoir stimulation and completions. Ernie holds more than 50 patents and has co-authored more than 35 technical publications. He holds a BS degree in geology from Colorado State University.

Christopher N. Fredd is the global unconventional assets business development manager at Schlumberger. He has more than 20 years of experience in the oil and gas industry, with roles spanning technology management, development, and implementation. Fredd holds a PhD degree in chemical engineering from the University of Michigan.


CHAPTER 12  FIELD IMPLEMENTATION OF HYDRAULIC FRACTURING

Lucas Bazan

Lucas W. Bazan is the president of Bazan Consulting Inc., a consulting firm specializing in hydraulic-fracture design and hydraulicfracturing
evaluation of tight gas, coalbed methane, and shale reservoirs. He holds a bachelor’s degree in physics from Texas State University and a bachelor’s degree in petroleum engineering from Texas A&M University.


CHAPTER 13  FRACTURING PRESSURE ANALYSIS

Bob Barree

Robert D. Barree is a Halliburton Technology Fellow and past-president and principal investigator of Barree & Associates, a consulting firm specializing in stimulation and well-performance optimization. He is a registered professional engineer and holds a BS degree in petroleum engineering from Pennsylvania State University and a PhD degree from Colorado School of Mines.


CHAPTER 14  FLOWBACK AND EARLY-TIME PRODUCTION DATA ANALYSIS

Chris Clarkson, Jesse Williams-Kovacs

Christopher R. Clarkson is a professor and holder of the Encana/Shell Chair in Unconventional Gas and Light Oil Research in the Department of Geoscience and an adjunct professor with the Department of Chemical and Petroleum Engineering at the University of Calgary. He leads the industry- and government-sponsored Tight Oil Consortium, which focuses on advanced reservoir characterization of unconventional light oil reservoirs in North America. Clarkson holds a PhD degree in geological engineering from the University of British Columbia. He is also a certified professional engineer with 11 years of industry experience as a petroleum (reservoir) engineer.

Jesse Williams-Kovacs is a research associate within the Tight Oil Consortium at the University of Calgary, focusing on flowback analysis.
He is also a petroleum engineer with Sproule, responsible for property evaluations and other consulting services with a focus on reservoir
engineering. He holds a BS degree in chemical engineering from Queen’s University, and MS and PhD degrees in petroleum reservoir engineering
from the University of Calgary. Williams-Kovacs is a certified professional engineer with 10 years of industry experience.


CHAPTER 15   FRACTURE DIAGNOSTICS

Norm Warpinski

Norm R. Warpinski served as a Technology Fellow at Halliburton in Houston, Texas, where he oversaw the development of new tools and analyses for hydraulic-fracture mapping, reservoir monitoring, hydraulic-fracture design and analysis, and integrated monitoring solutions for reservoir development. He retired from the company in July 2016. Warpinski holds a BS degree in mechanical engineering from Illinois Institute of Technology and MS and PhD degrees in mechanical engineering from the University of Illinois, Champaign/Urbana.


CHAPTER 16  ECONOMICS OF FRACTURING

Mark Pearson, Karen Olson

C. Mark Pearson is the president and chief executive officer of Liberty Resources LLC. He is an industry expert in the field of well completion and stimulation and is a pioneer of multistage hydraulic fracturing in horizontal wells. Pearson holds BS and PhD degrees from the Camborne School of Mines in the UK, and is a graduate of the Harvard Business School Advanced Management Program. He is an SPE Distinguished Member.

Karen E. Olson is the director of technology at Southwestern Energy. She has more than 30 years of industry experience, with a focus on the development and optimization of completions in various types of reservoirs. Olson holds a BS degree in petroleum engineering from Louisiana State University and an MS degree in petroleum engineering from Texas A&M University. She is an SPE Distinguished Member.


CHAPTER 17  ACID FRACTURING

Vibhas Pandey

Vibhas J. Pandey is an engineering fellow in the Global Completions Engineering Group at ConocoPhillips in Houston, Texas. He has more than 30 years of industry experience and has held lead positions in several disciplines, including drilling, workovers, well stimulation, and product development. Pandey holds BE and ME degrees in mechanical engineering from the National Institute of Technology in Surat, India, and an MS degree in petroleum engineering from the University of Oklahoma.


CHAPTER 18  REFRACTURING

Jennifer Miskimins, Kumar Ramurthy

Jennifer L. Miskimins is the associate department head and an associate professor in the Petroleum Engineering Department at the Colorado School of Mines. Her research interests focus on the areas of hydraulic fracturing, stimulation, completions, and unconventional reservoirs. Miskimins holds a BS degree in petroleum engineering from the Montana College of Mineral Science and Technology, and MS and PhD degrees in petroleum engineering from the Colorado School of Mines. She is an active member of SPE.

Muthukumarappan “Kumar” Ramurthy is the Director of Technology for North America at Halliburton, and has more than 20 years of industry experience in conventional/unconventional reservoirs and stimulation engineering. He holds a BE degree in mechanical engineering from India, an MS degree in petroleum engineering from Mississippi State University, and a PhD degree in petroleum engineering from the University of Wyoming.

Preface v
Acknowledgements vii

Chapter 1 – Introduction 1
1.1 What Has Changed Since Monograph 12 4
1.2 Geologic Considerations 5
1.3 Conventional vs. Unconventional Reservoirs 6
1.4 Horizontal vs. Vertical Wellbores 7
1.5 Other Types of Fracturing Stimulation 8
1.6 References 9

Chapter 2 – Pretreatment Formation Evaluation
2.1 Overview 13
2.2 Geologic Considerations 15
2.3 Acquiring Properties Using Wireline Logging 21
2.4 Core Analysis 29
2.5 Recap: How To Use These Data? 37
2.6 Nomenclature 38
2.7 References 39

Chapter 3 – Rock Mechanics and Fracture Geometry
3.1 Overview 47
3.2 Rock Properties 58
3.3 In-Situ Stress 61
3.4 Fracture-Height Growth in Geologic Media 66
3.5 Fracture Complexity 66
3.6 Summary 69
3.7 Nomenclature 69
3.8 References 70

Chapter 4 – Hydraulic Fracture Modeling 75
4.1 Introduction 76
4.2 Modeling Objectives 78
4.3 Basic Physical Principles in Fracture Propagation Models 82
4.4 Basic Fracture Modeling Concepts 85
4.5 1D and 2D Fracture Growth Models 88
4.6 The First Fracture Model Calibration Effort—Identifying Growth Behavior 90
4.7 Advanced Fracture Modeling Concepts I 92
4.8 Advanced 3D Fracture Growth Models 96
4.9 The Second Fracture Model Calibration Effort—Net-Pressure Matching 96
4.10 Advanced Fracture Modeling Concepts II 101
4.11 The Third Fracture Model Calibration Effort—Reconciliation With Fracture Diagnostics 103
4.12 Complex Fracture Models 113
4.13 Fully Coupled Geomechanical Fracture Models 120
4.14 Further Fracture Model Integration and Novel Developments 129
4.15 Fracture Modeling Advantages and Challenges 131
4.16 Thoughts on Future Use and Developments of Fracture Growth Models 133
4.17 Conclusions 135
4.18 Nomenclature 135
4.19 References 136

Chapter 5 – Proppants and Fracture Conductivity 143
5.1 Overview 144
5.2 Introduction 144
5.3 Effect of Fracture Conductivity on Well Performance 145
5.4 Commercial Proppants 146
5.5 Laboratory Measurements of Fracture Conductivity 152
5.6 Factors Affecting Fracture Conductivity—Proppant Characteristics and Fluids 154
5.7 Factors Affecting Fracture Conductivity—Interactions with the Reservoir 158
5.8 Nomenclature 162
5.9 References 162

Chapter 6 – Fracturing Fluids and Additives 165
6.1 Overview 166
6.2 Properties of a Viscous Fracturing Fluid 166
6.3 Water-Based Fracturing Fluids 167
6.4 Oil-Based Fracturing Fluids 174
6.5 Alcohol-Based Fracturing Fluids 174
6.6 Emulsion Fracturing Fluids 174
6.7 Foam-Based Fracturing Fluids 176
6.8 Energized Fracturing Fluids 178
6.9 Fracturing Fluid Additives 178
6.10 Waterfracs 184
6.11 References 185
6.12 Recommended Reading List 191

Chapter 7 – Fluid Leakoff 199
7.1 Overview 199
7.2 Introduction 200
7.3 Fluid-Leakoff Equation 200
7.4 Modeling of Leakoff Coefficient 210
7.5 Laboratory Measurements of Fluid-Loss Parameters 216
7.6 Effect of Key Parameters on Leakoff 219
7.7 Advances in Fluid-Loss Additives 223
7.8 Pressure-Dependent Leakoff 225
7.9 Nomenclature 226
7.10 References 229

Chapter 8 – Flow Behavior of Fracturing Fluids 233
8.1 Introduction 233
8.2 Rheology and Classification of Fluids 234
8.3 Rheological Characterization of Fracturing Fluids 235
8.4 Rheological Instrumentation 240
8.5 Perforation Friction Pressure Loss 241
8.6 Newtonian Fluid Flow in Straight Tubulars 246
8.7 Non-Newtonian Fluid Flow in Straight Tubulars 246
8.8 Newtonian Fluid Flow in Coiled Tubulars 252
8.9 Non-Newtonian Fluid Flow in Coiled Tubulars 253
8.10 Nomenclature 256
8.11 References 257

Chapter 9 – Proppant Transport 261
9.1 Overview 261
9.2 Introduction 261
9.3 Fundamentals of Proppant Transport 262
9.4 Proppant Transport Within the Fracture 265
9.5 Proppant Transport in Complex Fracture Network 278
9.6 Proppant Flowback 280
9.7 Nomenclature 285
9.8 References 285

Chapter 10 – Hydraulic Fracturing Treatment Design 291
10.1 Introduction 292
10.2 Outline 292
10.3 Key Influences 292
10.4 Fracturing-Treatment Design Process 294
10.5 Treatment Design Workflow 294
10.6 Key Input Data 294
10.7 Generating Log-Based Models for Fracture Simulators 295
10.8 Fracturing-Fluid Leakoff Calculations 295
10.9 Model Calibration 296
10.10 Stress and Rock-Property Calibration Process 296
10.11 Fracture Width Calculations 299
10.12 Well Productivity/Hydraulic Fracture Relationship 300
10.13 Material Selection: Fracturing Fluids 301
10.14 Foamed Fracturing Fluids 302
10.15 Material Selection: Proppants 304
10.16 NPV Calculations for Fracturing Treatments 305
10.17 Pump Schedule 307
10.18 Proppant-Concentration Schedule 308
10.19 Pump Schedule Generation 309
10.20 Tip-Screenout Design 312
10.21 Low-Viscosity-Fluid Design: Slickwater and Hybrid 312
10.22 Perforating for Hydraulic Fracturing 313
10.23 Limited-Entry Design 313
10.24 Fracturing-Treatment Design Cases: Pump Schedule 318
10.25 Design Approaches in Unconventional Shale Reservoirs 321
10.26 Comprehensive Fracturing-Treatment Design 325
10.27 Nomenclature 333
10.28 References 335

Chapter 11 – Well Completions 345
11.1 Overview 346
11.2 Introduction to Completions 347
11.3 Well Construction for Hydraulic Fracturing 347
11.4 Completion Strategies for Hydraulic Fracturing 367
11.5 Perforating for Hydraulic Fracturing 371
11.6 Multistage Placement Control and Treatment Diversion Techniques 383
11.7 Considerations for Selecting a Multistage Placement Control Technique 394
11.8 Additional Well Completion Considerations 398
11.9 Nomenclature 403
11.10 References 404

Chapter 12 – Field Implementation of Hydraulic Fracturing 415
12.1 Overview 416
12.2 Treatment Planning 417
12.3 Fracturing Equipment 418
12.4 Treatment Execution 434
12.5 Treating Pressure Interpretation 454
12.6 Treatment Redesign 463
12.7 Foam Fracturing 463
12.8 Acid Fracturing 477
12.9 Coalbed Methane Fracturing Applications 478
12.10 Environmental Considerations 482

12.11 Nomenclature 484
12.12 References 485

Chapter 13 – Fracturing Pressure Analysis 489
13.1 Overview 490
13.2 Components of Pumping Pressure 492
13.3 Prefracturing and Calibration Tests 495
13.4 Treating-Pressure Analysis 514
13.5 Application to Treatment Schedule Design and Modification 520
13.6 Nomenclature 520
13.7 References 521

Chapter 14 – Flowback and Early-Time Production Data Analysis 523
14.1 Introduction 524
14.2 RTA of Flowback and Early-Time Production Data 525

14.3 Case Studies 568
14.4 Summary, Discussion, and Current and Future Work 569
14.5 Nomenclature 576
14.6 Acknowledgments 580
14.7 References 580
Appendix 14.A 586
Appendix 14.B 588
Appendix 14.C 591
Appendix 14.D 594
Appendix 14.E 598
Appendix 14.F 606
Appendix 14.G 608
Appendix 14.H 611
Appendix 14.I 617

Chapter 15 – Fracture Diagnostics 625
15.1 Overview 625
15.2 Microseismic Monitoring 626

15.3 Surface Tiltmeter Monitoring 638
15.4 Downhole Tiltmeter Monitoring 641
15.5 Radioactive Proppant Tracers 644
15.6 Chemical Fracture Tracers (CFTs) 645
15.7 Distributed Fiber-Optic Sensing 647
15.8 Wellbore Imaging 651
15.9 Review 652
15.10 Nomenclature 653
15.11 References 654

Chapter 16 – Economics of Fracturing 57

16.1 Introduction 658
16.2 General Economic and Business Considerations 658
16.3 Conventional Reservoir Response to Fracture Penetration and Conductivity 660
16.4 Unconventional Reservoir Production Analysis 666
16.5 General Economic Parameters 669
16.6 Hydraulic Fracturing Treatment Costs 670
16.7 Conventional-Fracturing-Treatment Economics 674
16.8 Unconventional-Fracturing-Treatment Economics 681
16.9 Other Considerations 686
16.10 Summary 689
16.11 Nomenclature 689
16.12 References 690

Chapter 17 – Acid Fracturing 693
17.1 Introduction 694
17.2 Candidates for Acid Fracturing 694
17.3 Deciding Between Propped and Acid Fracturing 698
17.4 Acid/Mineral Reaction 699
17.5 Reaction Stoichiometry of Acids 699
17.6 Reaction Kinetics of Acids 705
17.7 Acid Mass Transfer 707
17.8 Acid Types in Well Stimulation 709
17.9 Modeling of Hydraulic Fractures 710
17.10 Acid Penetration 713
17.11 Acid-Fracture Conductivity 720
17.12 Acid-Fracturing-Treatment Design 724
17.13 Simulator-Based Acid-Fracturing Modeling 728
17.14 Nomenclature 732
17.15 References 737
Appendix 17.A: Acid-Fracturing-Treatment Design Example 742

Chapter 18 – Refracturing 753
18.1 Introduction 753
18.2 Case Histories of Refracturing Treatments 755
18.3 Determining the Need for Refracturing 761
18.4 Candidate Selection 763
18.5 Design Considerations 764
18.6 Conclusions 766
18.7 Nomenclature 766
18.8 References 766

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