Contents

Cover

Foreword

Part 1: Introduction

Chapter 1: Hydraulic Fracturing, An Overview
1. 1.1 What is Hydraulic Fracturing?
2. 1.2 Why Hydraulic Fracturing is Important
3. 1.3 Fracture Characterization
4. 1.4 Geomechanics of Hydraulic Fracturing
5. 1.5 Environmental Aspects of Hydraulic Fracturing
6. 1.6 Induced Seismicity
7. 1.7 Case Study: Fracturing Induced Seismicity in California
8. 1.8 Assessment of Global Oil and Gas Resources Amenable for Extraction via Hydraulic Fracturing
9. 1.9 Economics of HF
10. 1.10 Conclusions
11. Acknowledgement
12. References

Part 2: General Concepts

Chapter 2: Evolution of Stress Transfer Mechanisms During Mechanical Interaction Between Hydraulic Fractures and Natural Fractures
1. 2.1 Introduction
2. 2.2 Physical Model
3. 2.3 Mathematical Formulation
4. 2.4 Numerical Model
5. 2.5 Simulation Results
6. 2.6 Effect of Hydraulic Fracturing on Natural Fractures
7. 2.7 Conclusion
8. References
Chapter 3: Primer on Hydraulic Fracturing Concerning Initiatives on Energy Sustainability
1. 3.1 Hydraulic Fracturing
2. 3.2 Additional Types
3. 3.3 Other Most Common Objections to Drilling Operations
4. 3.4 Changes in Landscape and Beauty of Surroundings
5. 3.5 Increased Traffic
6. 3.6 Chemicals and Products on Locations
7. 3.7 Conclusion
8. Bibliography
Chapter 4: A Graph Theoretic Approach for Spatial Analysis of Induced Fracture Networks
1. 4.1 Background and Rationale
2. 4.2 Graph-Based Spatial Analysis
3. 4.3 Real World Applications of the Algorithm
4. 4.4 Discussion
5. 4.5 Conclusions
6. Acknowledgements
7. References

Part 3: Optimum Design Parameters

Chapter 5: Fracture Spacing Design for Multistage Hydraulic Fracturing Completions for Improved Productivity
1. 5.1 Introduction
2. 5.2 Method
3. 5.3 Data
4. 5.4 Results
5. 5.5 Concluding Remarks
6. Acknowledgements
7. References
Chapter 6: Clustering-Based Optimal Perforation Design Using Well Logs
1. 6.1 Introduction
2. 6.2 Objective and Motivation
3. 6.3 Technology
4. 6.4 Clustering Analysis
5. 6.5 Methodology and Analysis
6. 6.6 Applying the FCM Algorithm
7. 6.7 Results and Discussion
8. 6.8 Conclusions
9. Acknowledgements
10. References
Chapter 7: Horizontal Well Spacing and Hydraulic Fracturing Design Optimization: A Case Study on Utica-Point Pleasant Shale Play
1. 7.1 Introduction
2. 7.2 Methodology
3. 7.3 Optimization Scenarios
4. 7.4 Results and Discussion
5. 7.5 Conclusion
6. Acknowledgments
7. References

Part 4: Fracture Reservoir Characterization

Chapter 8: Geomechanical Modeling of Fault Systems Using the Material Point Method – Application to the Estimation of Induced Seismicity Potential to Bolster Hydraulic Fracturing Social License
1. 8.1 Introduction
2. 8.2 The Social License to Operate (SLO)
3. 8.3 Regional Faults in Oklahoma, USA and Alberta, Canada used as Input in Geomechanical Modeling
4. 8.4 Modeling Earthquake Potential using Numerical Material Models
5. 8.5 A New Workflow for Estimating Induced Seismicity Potential and its Application to Oklahoma and Alberta
6. 8.6 The Benefits of a Large Scale Predictive Model and Future Research
7. 8.7 Conflict of Interest
8. Acknowledgements
9. References
Chapter 9: Correlating Pressure with Microseismic to Understand Fluid-Reservoir Interactions During Hydraulic Fracturing
1. 9.1 Introduction
2. 9.2 Method
3. 9.3 Data
4. 9.4 Results
5. 9.5 Conclusions
6. 9.6 Acknowledgements
7. References
Chapter 10: Multigrid Fracture Stimulated Reservoir Volume Mapping Coupled with a Novel Mathematical Optimization Approach to Shale Reservoir Well and Fracture Design
1. 10.1 Introduction
2. 10.2 Problem Definition and Modeling
3. 10.3 Development of a New Mathematical Model
4. 10.4 Model Building
5. 10.5 Results and Discussions
6. 10.6 Conclusions and Recommendations
7. References
8. Appendix A: Abbreviations
9. Appendix B: Definition of the Fracturability Index Used in the Well Placement Process
10. Appendix C: Geometric Interpretation of Parameters Used in Building the Model
Chapter 11: A Semi-Analytical Model for Predicting Productivity of Refractured Oil Wells with Uniformly Distributed Radial Fractures
1. 11.1 Introduction
2. 11.2 Mathematical Model
3. 11.3 Model Verification
4. 11.4 Sensitivity Analysis
5. 11.5 Conclusions
6. Acknowledgements
7. References
8. Appendix A: Derivation of Infow Equation for Wells with Radial Fractures under Pseudo-Steady State Flow Conditions

Part 5: Environmental Issues of Hydraulic Fracturing

Chapter 12: The Role of Human Factors Considerations and Safety Culture in the Safety of Hydraulic Fracturing (Fracking)
1. 12.1 Introduction
2. 12.2 Benefits of Hydraulic Fracturing
3. 12.3 Common Criticisms
4. 12.4 Different Steps of Hydraulic Fracturing and Proposed Human Factors Considerations
5. 12.5 Hydraulic Fracturing Process: Drilling
6. 12.6 Hydraulic Fracturing Process: Fluid Injection
7. 12.7 Fracking Fluid
8. 12.8 Wastewater
9. 12.9 Human Factors and Safety Culture Considerations
10. 12.10 Examples of Recent Incidents
11. 12.11 Conclusion and Recommendations
12. Acknowledgment
13. References
Chapter 13: Flowback of Fracturing Fluids with Upgraded Visualization of Hydraulic Fractures and Its Implications on Overall Well Performance
1. 13.1 Introduction
2. 13.2 Assumptions
3. 13.3 Upgraded Visualization of Hydraulic Fracturing
4. 13.4 Reasons for Partial Flowback
5. 13.5 Impact of Parameters under Control
6. 13.6 Loss in Incremental Oil Production
7. 13.7 Conclusions
8. 13.8 Limitations
9. References
10. Appendix – A
Chapter 14: Assessing the Groundwater Contamination Potential from a Well in a Hydraulic Fracturing Operation
1. 14.1 Introduction
2. 14.2 Risk Pathways to the Shallow Groundwater
3. 14.3 Problem Statement
4. 14.4 Mathematical Formulation
5. 14.5 Hypothetical Case Description and the Numerical Method
6. 14.6 Results and Discussion
7. 14.7 Conclusion
8. References

Index

End User License Agreement

List of Illustrations

Chapter 1

Figure 1.1 An example of a typical HF configuration [1].
Figure 1.2 The explosion of shale production since 2010 [5].
Figure 1.3 Generation of fractures due to application of horizontal and vertical stress and...
Figure 1.4 Fracture mapping using MEQ, seismic, & petrophysical data using ANN-based...
Figure 1.5 The process of generating a 3D mesh of the domain for two-way coupled flow...
Figure 1.6 Numerical modeling to quantify risk factors for water contamination associated...
Figure 1.7 A comparison of induced seismicity in a field and laboratory setting with the...
Figure 1.8 All seismic events in study area, San Joaquin Valley, California (left), filtering...
Figure 1.9 Spatial variations in B-values in the study region. (Left), color coded number...

Chapter 2

Figure 2.1 Schematic of the physical domain used to study interaction between a hydraulic...
Figure 2.2 Time evolution of overpressure along HF calculated using the analytical solution...
Figure 2.3 Displacement field at t = 121 sec resulting from a balance of boundary...
Figure 2.4 Profiles of displacements and stress changes orthogonal (upper row) and parallel...
Figure 2.5 Time evolution of the effective stresses with opening of the hydraulic fracture...
Figure 2.6 Time evolution of slip (top row) and traction (bottom row) at the midpoints of...
Figure 2.7 Evolution of traction and slip on natural fractures due to opening and...
Figure 2.8 (a) Energy transfer from the hydraulic fracture to the natural fractures is...

Chapter 3

Graph 1 Volumetric percentages of additives in fracturing fluids from Modern Shale Gas Development in the United States.
Figure 3.1 Proppant size and placement. Courtesy of the authors.
Figure 3.2 Proppant shape. Courtesy of the authors.
Figure 3.3 Proppant hardness. Courtesy of the authors.

Chapter 4

Figure 4.1 Historical photograph of spatially dense wellbores in TItusville, PA...
Figure 4.2 A drawing of an example graph structure showing vertices (blue circles) and...
Figure 4.3 Workflow for preforming a graph analysis to spatially assess induced fractures.
Figure 4.4 Distribution and known status of wellbores within the Bradford Oil & Gas...
Figure 4.5 Representative graph output: Graph representation of wellbore points...
Figure 4.6 Location of Dayton Incident Well.
Figure 4.7 (a) Results of knn algorithm on Dayton PA area wellbore...

Chapter 5

Figure 5.1 Stage-wise distribution of microseismic derived (a) ‘b value...
Figure 5.2 (a) Microseismic derived ‘b value’, (b) image log derived...
Figure 5.3 Well #1 cross-section showing well track in reference to the varying lithologic...
Figure 5.4 (a) Modeled Poisson’s Ratio compared with actual log derived values and...
Figure 5.5 Validation results from a sample neural network training run showing minimized...
Figure 5.6 Optimal fuzzy set definitions based on training well data for (a) modeled...
Figure 5.7 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.8 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.9 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.10 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.11 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.12 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.13 Figure showing (a) the comparison between modeled fracture density and available...
Figure 5.14 (a) Well schematic showing localized sweet spot due to intersecting natural...

Chapter 6

Figure 6.1 Lost Hills field location.
Figure 6.2 Reservoir structure.
Figure 6.3 Field map showing the division of the three zones.
Figure 6.4 A snapshot of the sample data showing collected log tracks and perforation completion...
Figure 6.5 Clustering results by depth for two sample wells. In this figure, C1 represents...
Figure 6.6 3-month peak production vs. total perforation footages for all sampled wells.
Figure 6.7 3-month peak production vs. total perforation footages on good regions...
Figure 6.8 Fracture modeling. Proppant coverage at the end of pumping, perforations at...
Figure 6.9 Fracture modeling. Proppant coverage at the end of pumping, perforations at 2750...

Chapter 7

Figure 7.1 Reservoir top 3D model built in CMG-BUILDER. The drainage area covers 1,003...
Figure 7.2 Relative permeability curves for this study. These curves are modified from the...
Figure 7.3 Horizontal wells and planar hydraulic fracturing design.
Figure 7.4 The workflow for the well spacing and completion parameters optimization study.
Figure 7.5 The cumulative gas production, gas flow rate, and pressure distribution for...
Figure 7.6 Field cumulative gas production after 50 years for five drilling scenarios.
Figure 7.7 The results of net present value optimization study for five drilling scenarios.
Figure 7.8 Field recovery factor (RF) over different time periods for all the drilling...
Figure 7.9 Comparison of capital and operating costs with NPVs for different drilling...
Figure 7.10 Comparison of NPV between two costs of completion scenarios.
Figure 7.11 Field recovery factor comparison after 5 years between two completion costs...

Chapter 8

Figure 8.1 Diagrams showing the importance of credibility and trust in promoting social...
Figure 8.2 Fault map of Oklahoma [12]. These fault data are used as input to the...
Figure 8.3 Available earthquake and Underground Injection Control (UIC) well data from 2006...
Figure 8.4 (a) Extent of the Montney/Duvernay shale play and considered area of interest,...
Figure 8.5 (a) Coulombs stress change as computed by King & Cocco [7], (b) An...
Figure 8.6 Equivalent Fracture Models (EFM) derived from an area of interest in Oklahoma...
Figure 8.7 Result of the geomechanical proxy for ISP. Compared to historical earthquakes...
Figure 8.8 Zoom of Figure 8.7 that includes to the east the Prague fault, Oklahoma City...
Figure 8.9 Zoom of Figure 8.8.3 to show seismicity NE of interpreted fault in Major County.
Figure 8.10 (a) Equivalent Fracture Model derived from the major fault map of Figure 8.2d...
Figure 8.11 Derived ISP maps plotted along with injection volumes and earthquake data over...
Figure 8.12 Derived ISP maps plotted in an area of Alberta where multiple large magnitude...

Chapter 9

Figure 9.1 Nolte-Smith Interpretation Guide (log P_net vs. log T). Mode I indicat...
Figure 9.2 (a) Comparison of calculated BHP and estimated BHP (Eq. 9.10) and (b) observed...
Figure 9.3 Modeled modified Nolte-Smith exponent ‘e’. The region highlighted...
Figure 9.4 Gutenberg-Richter magnitude frequency relationship for earthquake data from...
Figure 9.5 Production data (fractional gas flow) compared with extensional diagnostic...
Figure 9.6 Production data (fractional gas flow) compared with extensional diagnostic...
Figure 9.7 Microseismic derived b-value compared with extensional diagnostic parameters...
Figure 9.8 Microseismic derived b-value compared with extensional diagnostic parameters...
Figure 9.9 OBMI log derived fracture density compared with extensional diagnostic...
Figure 9.10 Modeled exponent ‘e’ for two stage treatments during proppant...
Figure 9.11 Results from b-value analysis for (a) stage A’ and (b) stage...

Chapter 10

Figure 10.1 Fracture network length as a function of fluid volume injected for five vertical...
Figure 10.2 Multigrid based SRV.
Figure 10.3 First recommended flowchart to be used as a utility in the optimization process...
Figure 10.4 Second recommended approach of optimization process.
Figure 10.5 Four different SRV’s are located, whether staggered, or staggered and...
Figure 10.6 Drainage volume for different SRV for different fracture stages branched out...
Figure 10.7 One Horizontal well passes through four different SRV’s. Model domain...
Figure 10.8 Combination of 4 wells and SRV for the model before optimization, where the...
Figure 10.9 Fracturability index distribution for the middle layer in the 80 × 80...
Figure 10.10 A comparison between SRV, before and after applying the filter of FI. Note that...
Figure 10.11 Optimized placement of the same size SRV versus uniform distribution of SRV...
Figure A10.12 Combination of 5 wells originating from one well pad.
Figure A10.13 Stimulated reservoir volume (SRV) for one fracture stage.
Figure A10.14 Basic network connections in a well.
Figure A10.15 Hydraulic Fracture stage nodes representation.
Figure A10.16 Valid versus invalid nodes for fracture stage.
Figure A10.17 Three-dimensional representation of fracture intersection constraints.
Figure A10.18 Valid paths for neighboring wells.
Figure A10.19 Fracture stage parameters.
Figure A10.20 Discretized SRV for one fracture stage.

Chapter 11

Figure 11.1 Sketch of radial fractures around a refractured vertical well.
Figure 11.2 Calculated effect of number of fractures on well productivity.
Figure 11.3 Calculated effect of fracture conductivity on well productivity.
Figure A11.1 A plan view of fractures around a wellbore.

Chapter 12

Figure 12.1 Total U.S. natural gas production, consumption, and net imports in the reference...
Figure 12.2 Hydraulic fracturing steps (inspired from [28]) and related major human factors.
Figure 12.3 View of vertical and horizontal drilling [30].
Figure 12.4 Drilling rig components [26].
Figure 12.5 Drilling rig floor hazardous area layout with tong swing radius [31].
Figure 12.6 Components of the well perforation process [30].
Figure 12.7 Major subsystems of a technological system.
Figure 12.8 Risks/loses and impacts of fracking mishaps and accidents (adapted from [48]).
Figure 12.9 Well cross-section schematic [50].

Chapter 13

Figure 13.1 CFD simulation of water within 7 mm Belgian Sandstone [7].
Figure 13.2 Narrowing down of capillary tubes, HiWAY by Schlumberger [8].
Plot 13.1 Comparison of change in throughput.
Plot 13.2 Fracture half-length vs. depth of penetration.
Plot 13.3 µ vs. recoverable oil volume.
Plot 13.4 Time vs. additional irrecoverable fracturing fluid volume.
Plot 13.5 Decline curve.

Chapter 14

Figure 14.1 Schematic representation of failure in vertical pipe and contamination plume in...
Figure 14.2 Random simulations workflow.
Figure 14.3 Cumulative distribution functions (CDFs) of concentration value in the monitorin...
Figure 14.4 Cumulative distribution functions (CDFs) of concentration value in the monitoring...
Figure 14.5 Arrival time CDF – Uniform (a) and Poisson’s (b) PDFs for the...

List of Tables

Chapter 4

Table 4.1 Literature derived values for the average fracture radii for a bounding litholog...

Chapter 7

Table 7.1 Reservoir characteristics of the base reservoir model.
Table 7.2 Economic analysis inputs.
Table 7.3 Five scenarios of inter-lateral spacing and the corresponding well spacing over...
Table 7.4 Range of completion parameters.
Table 7.5 Optimized completion parameters.
Table 7.6 Optimized completion parameters for the completion cost scenario of $200K per...

Chapter 10

Table 10.1 Parameters of the reservoir model used in validating the developed model.
Table 10.2 Properties of the reservoir model used in validating the developed model.

Chapter 11

Table 11.1 Estimated reservoir and fracture properties in the Naricual-5 formation.

Chapter 14

Table 14.1 Parameters of the model.
Table 14.2 Parameters of the random simulations.
Table 14.3 Probabilities calculated for different scenarios.
Table 14.4 Statistics of arrival time (years).

This edition first published 2019 by John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, USA and Scrivener Publishing LLC, 100 Cummings Center, Suite 541J, Beverly, MA 01915, USA
© 2019 Scrivener Publishing LLC
For more information about Scrivener publications please visit www.scrivenerpublishing.com.

All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or other wise, except as permitted by law. Advice on how to obtain permission to reuse material from this title is available at http://www.wiley.com/go/permissions.

Wiley Global Headquarters
111 River Street, Hoboken, NJ 07030, USA

For details of our global editorial offices, customer services, and more information about Wiley products visit us at www.wiley.com.

Limit of Liability/Disclaimer of Warranty
While the publisher and authors have used their best efforts in preparing this work, they make no representations or warranties with respect to the accuracy or completeness of the contents of this work and specifically disclaim all warranties, including without limitation any implied warranties of merchantability or fitness for a particular purpose. No warranty may be created or extended by sales representatives, written sales materials, or promotional statements for this work. The fact that an organization, website, or product is referred to in this work as a citation and/or potential source of further information does not mean that the publisher and authors endorse the information or services the organization, website, or product may provide or recommendations it may make. This work is sold with the understanding that the publisher is not engaged in rendering professional services. The advice and strategies contained herein may not be suitable for your situation. You should consult with a specialist where appropriate. Neither the publisher nor authors shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages. Further, readers should be aware that websites listed in this work may have changed or disappeared between when this work was written and when it is read.

Library of Congress Cataloging-in-Publication Data

ISBN 978-1-119-55569-8

Foreword

Since its inception in 1947, hydraulic fracturing has had a greater influence on hydrocarbon production than any other technology. Drilling and fracturing of horizontal wells starting in the late 1980’s enabled further increases in production. The oil industry took the new technology to a new level, creating the shale revolution, making the USA the world’s largest producer of crude oil.

The advancement of technology also brought new challenges in technological, environmental, human, and geopolitical dimensions. Each challenge will have to be understood and addressed. This book collects papers that address the environmental and human dimensions in simple terms in order to clarify issues and dispel misconceptions.

Exploring the technological dimension, the book includes chapters that address many of the issues that are very unique to unconventional reservoirs, including chapters on Reservoir-Fluid interaction, optimization of fracture spacing, and optimization of fracture placement.

M. Y. Soliman, PhD, PE, NAI

Chair of the Petroleum Engineering Department

William C Miller Endowed Chair

The University of Houston

Hydraulic Fracturing and Well Stimulation

Foreword

Part 1
INTRODUCTION