and a contribution from Offshore Europe

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1 Primary funding is provided by The SPE Foundation through member donations and a contribution from Offshore Europe The Society is grateful to those companies that allow their professionals to serve as lecturers Additional support provided by AIME Society of Petroleum Engineers Distinguished Lecturer Program

2 Completion of Hydrocarbon Bearing Shale Reservoirs George Waters Schlumberger Society of Petroleum Engineers Society of Petroleum Engineers Distinguished Lecturer Program

3 Evolution of US Shales Initially driven by desportion Focus shifts to pore gas Deeper Higher Reservoir Pressures Dramatic increase in production ~1 BCF/day in BCF/day in 2009 Number of Producing Shale Gas Well s Annual Shale Gas Pro oduction, Bcf 60,000 60k 50,000 50k 40,000 40k 30,000 30k 20,000 20k 10,000 10k Marcellus Shale Shale Haynesville Shale Shale Woodford Shale Shale Fayetteville Shale Shale New Albany Shale Shale Lewis Shale Shale Barnett Shale Shale Antrim Shale Shale Ohio Shale Shale ,500 Marcellus Shale Shale Haynesville Shale Shale Woodford Shale Shale ,000 Fayetteville Shale Shale New Albany Shale Shale Lewis Shale Shale Barnett Shale Shale ,500 Antrim Shale Shale Ohio Shale Shale ,

4 Shale in Perspective: Permeability Arab-D Carbonate Berea Sand Brick Jonah Lance Fm. Organic Shale Salt Unconventional e-06 md 100 nd = D

5 Shale Stimulation Requirements: Closely Spaced Fractures Extremely Low Matrix Permeabilities Majority of Pressure Drop at Fracture Face At Initial Reservoir Pressure 10s of feet from fracture for years Hydraulic Fracture Complexity induces pressure drop from multiple points Horizontal Wells Frequently Employed Drilled in direction of s h 10 Year Pressure Profile Generate multiple, transverse hydraulic fractures

6 Pressure Profile After 30 years with 30 Acre Well Spacing 3500 B1 : 1 1 B3 : B2 : 1 1 B1 : 1 1 B5 : 1 1 B6 : 1 1 B4 : 1 1 B3 : 1 1 B8 : 1 1 B4 : Dense Fracture Patterns Required via Closely Spaced Vertical Wells or Horizontal Wells B2 : 1 1 B7 : Pressure Profile After 30 years with 15 Acre Well Spacing

7 Lateral Landing Example Best Petrophysics φ, k, GIP Mineralogy Lowest Clay Volume Borehole Stability Breakout Expandable Clays Stress Lowest Closure Stress Optimum Landing Points Frac Simulations to Quantify

8 In-situ Stress Direction Induced Fractures, Borehole Breakout, Sonic Logs, & Microseismic Induced Fractures oriented in σ H direction Breakout oriented in σ h direction Microseismic events orient in σ H direction

9 Calibration of In-Situ Stress Isotropic Stress Profile versus Anisotropic Stress Profile Isotropic Stress Anisotropic Stress

10 Barnett Shale Fracture Geometry Arkoma Shale Fracture Geometry Natural Fractures normal to σ H Low Horizontal Stress Anisotropy Wide Hydraulic Fracture Networks Natural Fractures Parallel to σ H High Horizontal Stress Anisotropy Narrow Hydraulic Fracture Network Lateral Azimuth = σ H Vertical Well

11 Spacing of Hydraulically Fractures Example: Young s Modulus = 3x10 6 psi Hydraulic Width = in Spacing Stress Increase (ft) (psi) 1 12, , w = Δb w=δb ε =w/b b b Hooke s Law Δσ = Ε ε = Ε w/b

12 Simultaneous Hydraulic Fracturing In-situ Pulverization SPE

13 Simultaneously Hydraulically Fracturing Results 1,000, ,000 Ra ate [mscfd], Gas [mscf] 10,000 1, Days Initial Gas Simulfrac Gas Simul Cum Initial Cum

14 The Role of Effective Stress Do We Need Proppant? Force acting on fracture systems σ = σ - αp f Barnett Shale Example D = 7,000 ft P r = 0.55 psi/ft σ h = 0.60 psi/ft P wf = 500 psi σ H = 0.65 psi/ft Initial Conditions σ h = 350 psi σ H = 700 psi Δσ H-h = 350 psi During Production σ h = 3,700 psi σ H = 4,050 psi Haynesville Shale Example D = 11,000 ft P r = 0.85 psi/ft σ h = 0.95 psi/ft P wf = 7,500 psi σ H = 1.00 psi/ft P wf = 3,000 psi Initial Conditions During Production σ h = 1,100 psi σ h = 2,950 psi σ H = 1,650 psi σ H = 3,500 psi Δσ H-h = 550 psi σ h = 7,450 psi σ H = 8,000 psi Permeability (md) Haynesville early Production Barnett 5 MMPSI, 1.0 lb/ft2 5MMPSI MMPSI, lb/ft2 5 MMPSI, 0.25 lb/ft2 2 MMPSI, 1.0 lb/ft2 2 MMPSI, 0.5 lb/ft2 2 MMPSI, 0.25 lb/ft2 1 MMPSI, 1.0 lb/ft2 1 MMPSI, 0.5 lb/ft2 1 MMPSI, 0.25 lb/ft2 Haynesville late Production Stress on Proppant

15 Fracturing Fluid Selection Slickwater More Surface Area/Unit Cost Wider Fracture Fairways Gels Fracture Initiation Crosslinked Gel Frac SPE Foams Low Pore Pressure Swelling Clays Water Shortages Diversion Fibers, Ball Sealers, Sand Slugs Simul-fracs, Zipper-fracs, Refracs Slickwater Refrac Propped Fractures SPE Propped Fractures Effective Frac Conductivity Prop Volume, Viscous Fluids, Light Weight Props, Foams

16 Fracturing Fluid Additives Salts Shale Compatibility Swelling Clays Scale Inhibitors Mixed/Reused Waters High TDS Waters Surfactants CST Ra atio Impact Wetting Phase 5.0 Exacerbate Imbibition Oil or Non-Wetting Bactericides Untreated Water Breakers High MW Polymers oy Iron Stabilizers Chlorite & Pyrite Barite KCl [%]

17 Perforation Practices Impact on NWB Complexity Longer Perforation Clusters Can induce Parallel Fracturing High Density Phasing Tortuous Path leaving the Wellbore Limited Entry Design Perf Clusters per Frac Stage PerfCluster Spacing Can create Fracture Interference Perforation Performance Hard Rocks Shorter Penetration ti Argillaceous Rocks Collapsed Tunnels Sand Jetting Deeper Penetration Physically Remove Rock Single Plane Phasing σ v σ H σ H Colinear Fracture Aligned along Wellbore Axis Secondary & Multiple Competing Fractures Colinear Frac Projection Δp perf Surface = c 1.98 Q 2 Main Fracture d 4 p 2 N ρ 2 p Wellhead Perforations Projection of Main Fracture Projection of Secondary & Multiple Competing Fractures Wellbore Projection

18 Summary Keys to Optimizing i i Shale Gas Completions: Identify Stimulation Drivers Fracture Height Growth & Complexity Fracture Conductivity & Fluid Compatibility Must Perform Science At Beginning of Development 3D Seismic Acquisition to understand Structure Core Analysis for Mechanical Properties, Conductivity & Fluids Testing Log Analysis to quantify Petrophysics and Geomechanics Microseismic Monitoring to Quantify Hydraulic Fracture Geometry Evolves to Manufacturing Process Maximize Drilling Efficiency Optimize Well Spacing & Completion Process Change Process as Acreage Changes Continually Learn as Project Evolves

19 Key Parameters for Shale Plays Geology Thermal maturity Organic richness Mineralogy Matrix permeability Thickness Porosity Fluid saturations Hydrocarbons in place Faults and fractures Adjacent water bearing formations Engineering Stress field and magnitude Frac height growth Frac orientation Hydraulic vs. natural Frac complexity Frac conductivity Fluid compatibility

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