Author: Kun Sang Lee
Publisher: Gulf Professional Publishing
ISBN: 0128178612
Category : Technology & Engineering
Languages : en
Pages : 152
Book Description
Transport in Shale Reservoirs fills the need for a necessary, integrative approach on shale reservoirs. It delivers both the fundamental theories of transport in shale reservoirs and the most recent advancements in the recovery of shale oil and gas in one convenient reference. Shale reservoirs have distinctive features dissimilar to those of conventional reservoirs, thus an accurate evaluation on the behavior of shale gas reservoirs requires an integrated understanding on their characteristics and the transport of reservoir and fluids. - Updates on the various transport mechanisms in shale, such as molecular diffusion and phase behavior in nano-pores - Applies theory to practice through simulation in both shale oil and gas - Presents an up-to-date reference on remaining challenges, such as organic material in the shale simulation and multicomponent transport in CO2 injection processes
Transport in Shale Reservoirs
Author: Kun Sang Lee
Publisher: Gulf Professional Publishing
ISBN: 0128178612
Category : Technology & Engineering
Languages : en
Pages : 152
Book Description
Transport in Shale Reservoirs fills the need for a necessary, integrative approach on shale reservoirs. It delivers both the fundamental theories of transport in shale reservoirs and the most recent advancements in the recovery of shale oil and gas in one convenient reference. Shale reservoirs have distinctive features dissimilar to those of conventional reservoirs, thus an accurate evaluation on the behavior of shale gas reservoirs requires an integrated understanding on their characteristics and the transport of reservoir and fluids. - Updates on the various transport mechanisms in shale, such as molecular diffusion and phase behavior in nano-pores - Applies theory to practice through simulation in both shale oil and gas - Presents an up-to-date reference on remaining challenges, such as organic material in the shale simulation and multicomponent transport in CO2 injection processes
Publisher: Gulf Professional Publishing
ISBN: 0128178612
Category : Technology & Engineering
Languages : en
Pages : 152
Book Description
Transport in Shale Reservoirs fills the need for a necessary, integrative approach on shale reservoirs. It delivers both the fundamental theories of transport in shale reservoirs and the most recent advancements in the recovery of shale oil and gas in one convenient reference. Shale reservoirs have distinctive features dissimilar to those of conventional reservoirs, thus an accurate evaluation on the behavior of shale gas reservoirs requires an integrated understanding on their characteristics and the transport of reservoir and fluids. - Updates on the various transport mechanisms in shale, such as molecular diffusion and phase behavior in nano-pores - Applies theory to practice through simulation in both shale oil and gas - Presents an up-to-date reference on remaining challenges, such as organic material in the shale simulation and multicomponent transport in CO2 injection processes
Fundamentals of Gas Shale Reservoirs
Author: Reza Rezaee
Publisher: John Wiley & Sons
ISBN: 1119039266
Category : Technology & Engineering
Languages : en
Pages : 417
Book Description
Provides comprehensive information about the key exploration, development and optimization concepts required for gas shale reservoirs Includes statistics about gas shale resources and countries that have shale gas potential Addresses the challenges that oil and gas industries may confront for gas shale reservoir exploration and development Introduces petrophysical analysis, rock physics, geomechanics and passive seismic methods for gas shale plays Details shale gas environmental issues and challenges, economic consideration for gas shale reservoirs Includes case studies of major producing gas shale formations
Publisher: John Wiley & Sons
ISBN: 1119039266
Category : Technology & Engineering
Languages : en
Pages : 417
Book Description
Provides comprehensive information about the key exploration, development and optimization concepts required for gas shale reservoirs Includes statistics about gas shale resources and countries that have shale gas potential Addresses the challenges that oil and gas industries may confront for gas shale reservoir exploration and development Introduces petrophysical analysis, rock physics, geomechanics and passive seismic methods for gas shale plays Details shale gas environmental issues and challenges, economic consideration for gas shale reservoirs Includes case studies of major producing gas shale formations
Shale Gas and Tight Oil Reservoir Simulation
Author: Wei Yu
Publisher: Gulf Professional Publishing
ISBN: 0128138696
Category : Science
Languages : en
Pages : 432
Book Description
Shale Gas and Tight Oil Reservoir Simulation delivers the latest research and applications used to better manage and interpret simulating production from shale gas and tight oil reservoirs. Starting with basic fundamentals, the book then includes real field data that will not only generate reliable reserve estimation, but also predict the effective range of reservoir and fracture properties through multiple history matching solutions. Also included are new insights into the numerical modelling of CO2 injection for enhanced oil recovery in tight oil reservoirs. This information is critical for a better understanding of the impacts of key reservoir properties and complex fractures. - Models the well performance of shale gas and tight oil reservoirs with complex fracture geometries - Teaches how to perform sensitivity studies, history matching, production forecasts, and economic optimization for shale-gas and tight-oil reservoirs - Helps readers investigate data mining techniques, including the introduction of nonparametric smoothing models
Publisher: Gulf Professional Publishing
ISBN: 0128138696
Category : Science
Languages : en
Pages : 432
Book Description
Shale Gas and Tight Oil Reservoir Simulation delivers the latest research and applications used to better manage and interpret simulating production from shale gas and tight oil reservoirs. Starting with basic fundamentals, the book then includes real field data that will not only generate reliable reserve estimation, but also predict the effective range of reservoir and fracture properties through multiple history matching solutions. Also included are new insights into the numerical modelling of CO2 injection for enhanced oil recovery in tight oil reservoirs. This information is critical for a better understanding of the impacts of key reservoir properties and complex fractures. - Models the well performance of shale gas and tight oil reservoirs with complex fracture geometries - Teaches how to perform sensitivity studies, history matching, production forecasts, and economic optimization for shale-gas and tight-oil reservoirs - Helps readers investigate data mining techniques, including the introduction of nonparametric smoothing models
Geomechanical Studies of the Barnett Shale, Texas, USA
Author: John Peter Vermylen
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 143
Book Description
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.
Publisher: Stanford University
ISBN:
Category :
Languages : en
Pages : 143
Book Description
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.
Petrophysical Characterization and Fluids Transport in Unconventional Reservoirs
Author: Jianchao Cai
Publisher: Elsevier
ISBN: 0128172894
Category : Technology & Engineering
Languages : en
Pages : 354
Book Description
Petrophysical Characterization and Fluids Transport in Unconventional Reservoirs presents a comprehensive look at these new methods and technologies for the petrophysical characterization of unconventional reservoirs, including recent theoretical advances and modeling on fluids transport in unconventional reservoirs. The book is a valuable tool for geoscientists and engineers working in academia and industry. Many novel technologies and approaches, including petrophysics, multi-scale modelling, rock reconstruction and upscaling approaches are discussed, along with the challenge of the development of unconventional reservoirs and the mechanism of multi-phase/multi-scale flow and transport in these structures. - Includes both practical and theoretical research for the characterization of unconventional reservoirs - Covers the basic approaches and mechanisms for enhanced recovery techniques in unconventional reservoirs - Presents the latest research in the fluid transport processes in unconventional reservoirs
Publisher: Elsevier
ISBN: 0128172894
Category : Technology & Engineering
Languages : en
Pages : 354
Book Description
Petrophysical Characterization and Fluids Transport in Unconventional Reservoirs presents a comprehensive look at these new methods and technologies for the petrophysical characterization of unconventional reservoirs, including recent theoretical advances and modeling on fluids transport in unconventional reservoirs. The book is a valuable tool for geoscientists and engineers working in academia and industry. Many novel technologies and approaches, including petrophysics, multi-scale modelling, rock reconstruction and upscaling approaches are discussed, along with the challenge of the development of unconventional reservoirs and the mechanism of multi-phase/multi-scale flow and transport in these structures. - Includes both practical and theoretical research for the characterization of unconventional reservoirs - Covers the basic approaches and mechanisms for enhanced recovery techniques in unconventional reservoirs - Presents the latest research in the fluid transport processes in unconventional reservoirs
Petrophysics
Author: Erle C. Donaldson
Publisher: Elsevier
ISBN: 0080497659
Category : Technology & Engineering
Languages : en
Pages : 916
Book Description
The petroleum geologist and engineer must have a working knowledge of petrophysics in order to find oil reservoirs, devise the best plan for getting it out of the ground, then start drilling. This book offers the engineer and geologist a manual to accomplish these goals, providing much-needed calculations and formulas on fluid flow, rock properties, and many other topics that are encountered every day. New updated material covers topics that have emerged in the petrochemical industry since 1997. - Contains information and calculations that the engineer or geologist must use in daily activities to find oil and devise a plan to get it out of the ground - Filled with problems and solutions, perfect for use in undergraduate, graduate, or professional courses - Covers real-life problems and cases for the practicing engineer
Publisher: Elsevier
ISBN: 0080497659
Category : Technology & Engineering
Languages : en
Pages : 916
Book Description
The petroleum geologist and engineer must have a working knowledge of petrophysics in order to find oil reservoirs, devise the best plan for getting it out of the ground, then start drilling. This book offers the engineer and geologist a manual to accomplish these goals, providing much-needed calculations and formulas on fluid flow, rock properties, and many other topics that are encountered every day. New updated material covers topics that have emerged in the petrochemical industry since 1997. - Contains information and calculations that the engineer or geologist must use in daily activities to find oil and devise a plan to get it out of the ground - Filled with problems and solutions, perfect for use in undergraduate, graduate, or professional courses - Covers real-life problems and cases for the practicing engineer
Unconventional Reservoir Geomechanics
Author: Mark D. Zoback
Publisher: Cambridge University Press
ISBN: 1107087074
Category : Business & Economics
Languages : en
Pages : 495
Book Description
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.
Publisher: Cambridge University Press
ISBN: 1107087074
Category : Business & Economics
Languages : en
Pages : 495
Book Description
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.
Deep Shale Oil and Gas
Author: James G. Speight
Publisher: Gulf Professional Publishing
ISBN: 0128030984
Category : Technology & Engineering
Languages : en
Pages : 494
Book Description
Natural gas and crude oil production from hydrocarbon rich deep shale formations is one of the most quickly expanding trends in domestic oil and gas exploration. Vast new natural gas and oil resources are being discovered every year across North America and one of those new resources comes from the development of deep shale formations, typically located many thousands of feet below the surface of the Earth in tight, low permeability formations. Deep Shale Oil and Gas provides an introduction to shale gas resources as well as offer a basic understanding of the geomechanical properties of shale, the need for hydraulic fracturing, and an indication of shale gas processing. The book also examines the issues regarding the nature of shale gas development, the potential environmental impacts, and the ability of the current regulatory structure to deal with these issues. Deep Shale Oil and Gas delivers a useful reference that today's petroleum and natural gas engineer can use to make informed decisions about meeting and managing the challenges they may face in the development of these resources. - Clarifies all the basic information needed to quickly understand today's deeper shale oil and gas industry, horizontal drilling, fracture fluids chemicals needed, and completions - Addresses critical coverage on water treatment in shale, and important and evolving technology - Practical handbook with real-world case shale plays discussed, especially the up-and-coming deeper areas of shale development
Publisher: Gulf Professional Publishing
ISBN: 0128030984
Category : Technology & Engineering
Languages : en
Pages : 494
Book Description
Natural gas and crude oil production from hydrocarbon rich deep shale formations is one of the most quickly expanding trends in domestic oil and gas exploration. Vast new natural gas and oil resources are being discovered every year across North America and one of those new resources comes from the development of deep shale formations, typically located many thousands of feet below the surface of the Earth in tight, low permeability formations. Deep Shale Oil and Gas provides an introduction to shale gas resources as well as offer a basic understanding of the geomechanical properties of shale, the need for hydraulic fracturing, and an indication of shale gas processing. The book also examines the issues regarding the nature of shale gas development, the potential environmental impacts, and the ability of the current regulatory structure to deal with these issues. Deep Shale Oil and Gas delivers a useful reference that today's petroleum and natural gas engineer can use to make informed decisions about meeting and managing the challenges they may face in the development of these resources. - Clarifies all the basic information needed to quickly understand today's deeper shale oil and gas industry, horizontal drilling, fracture fluids chemicals needed, and completions - Addresses critical coverage on water treatment in shale, and important and evolving technology - Practical handbook with real-world case shale plays discussed, especially the up-and-coming deeper areas of shale development
Hydraulic Fracturing in Unconventional Reservoirs
Author: Hoss Belyadi
Publisher: Gulf Professional Publishing
ISBN: 0128176660
Category : Technology & Engineering
Languages : en
Pages : 636
Book Description
Hydraulic Fracturing in Unconventional Reservoirs: Theories, Operations, and Economic Analysis, Second Edition, presents the latest operations and applications in all facets of fracturing. Enhanced to include today's newest technologies, such as machine learning and the monitoring of field performance using pressure and rate transient analysis, this reference gives engineers the full spectrum of information needed to run unconventional field developments. Covering key aspects, including fracture clean-up, expanded material on refracturing, and a discussion on economic analysis in unconventional reservoirs, this book keeps today's petroleum engineers updated on the critical aspects of unconventional activity. - Helps readers understand drilling and production technology and operations in shale gas through real-field examples - Covers various topics on fractured wells and the exploitation of unconventional hydrocarbons in one complete reference - Presents the latest operations and applications in all facets of fracturing
Publisher: Gulf Professional Publishing
ISBN: 0128176660
Category : Technology & Engineering
Languages : en
Pages : 636
Book Description
Hydraulic Fracturing in Unconventional Reservoirs: Theories, Operations, and Economic Analysis, Second Edition, presents the latest operations and applications in all facets of fracturing. Enhanced to include today's newest technologies, such as machine learning and the monitoring of field performance using pressure and rate transient analysis, this reference gives engineers the full spectrum of information needed to run unconventional field developments. Covering key aspects, including fracture clean-up, expanded material on refracturing, and a discussion on economic analysis in unconventional reservoirs, this book keeps today's petroleum engineers updated on the critical aspects of unconventional activity. - Helps readers understand drilling and production technology and operations in shale gas through real-field examples - Covers various topics on fractured wells and the exploitation of unconventional hydrocarbons in one complete reference - Presents the latest operations and applications in all facets of fracturing
Development of Unconventional Reservoirs
Author: Reza Rezaee
Publisher: MDPI
ISBN: 3039285807
Category : Science
Languages : en
Pages : 522
Book Description
The need for energy is increasing and but the production from conventional reservoirs is declining quickly. This requires an economically and technically feasible source of energy for the coming years. Among some alternative future energy solutions, the most reasonable source is from unconventional reservoirs. As the name “unconventional” implies, different and challenging approaches are required to characterize and develop these resources. This Special Issue covers some of the technical challenges for developing unconventional energy sources from shale gas/oil, tight gas sand, and coalbed methane.
Publisher: MDPI
ISBN: 3039285807
Category : Science
Languages : en
Pages : 522
Book Description
The need for energy is increasing and but the production from conventional reservoirs is declining quickly. This requires an economically and technically feasible source of energy for the coming years. Among some alternative future energy solutions, the most reasonable source is from unconventional reservoirs. As the name “unconventional” implies, different and challenging approaches are required to characterize and develop these resources. This Special Issue covers some of the technical challenges for developing unconventional energy sources from shale gas/oil, tight gas sand, and coalbed methane.