Horizontal Fracturing in Shale Plays Matt McKeon

1. Horizontal Fracturing in Shale PlaysMatt McKeon

2. Shortening the learning curve Quantify Construct Complete Analyze • Historically: a trial-and-error process • Data acquisition • USA analog fields can speed up evaluation and development

3. Recent plays: fracture stimulations are evolving • Hybrid/Conv • 12-15 Stages • 40-60 BPM • 3-4 MM lbs prop (total) • 30/60, 20/40 • 3-4 ppg • 4 MM Gal • 25,000 HHP • 250-300’/Stage • WaterFracs • 8-10 Stages • 80-100 BPM • 1.5 MM lbs prop • 100 Mesh, 40/70 • 1 ppg Max • 7 MM Gal • 40,000 HHP • 350-450’/Stage 2008 2009 2010 Eagle Ford

4. Even Barnett stimulation is still changing

5. Shale Gas Development Process WorkflowData Acquisition 5

6. Shale parameters to enhance commercial production • Gas content : > 100 scf/ton • Thermal maturity (Ro) : 0.7 to 2.5+ range; 1.2 typical • Permeability : greater than 100 nanodarcies • Porosity : > 4% • Pressure : above normal • TOC : > 2% • Water saturation : < 45% • Well bounded & thick zone : > 100 ft • Moderate clay content : < 40% • Well bounded : i.e. good fracbarriers • Brittle shale (fracability) : i.e. low Poisson’s & high YM • Natural fractures : moderate presence

7. Analog Analysis

8. U.S. shale play: choose stimulation Analog Analysis

9. Shale Analysis Log Reservoir Properties Brittle or Ductile? Unconfined Compressive Strength Mineralology Lithology Kerogen Content Natural Fractures? Hydrocarbon Content Frac “Ease” Shale Type TOC SPE 115258 • Where would you perforate? • What is the TOC and gas content? • Will it frac and what is the relative fracture width and barriers? • What is the shale volumetric gas in place? • What is the shale porosity and permeability? • Where is the organic rich shale? • Where are the zones of highest kerogen content

10. Shale fracturing simulation • Designed for complex fracturing • Couple available data with microseismic to optimize fluid system and frac design • Recalibrate model based on post job analyses and regional variations

11. OBJECTIVEMaximize stimulated reservoir volume (SRV)

12. Shale fracture characteristics To create complexity you must have: Pre-existing natural fissures Low differential horizontal stresses (net pressure > σm) Brittleness Ductile Brittle • Woodford • Bakken • Marcellus • Tight Gas Sands • Haynesville • Eagleford • Barnett

13. Shale Completion Strategy: Based on Formation Brittleness & Liquid Production SPE 115258

14. Shale fluid decisions 14

15. Lateral design, stage intervals & well spacing • Lateral • Drilled in direction on minimum horizontal stress for transverse fracturing • Greater than 90 degree deviation is common practice • Stay in best portion of the reservoir while drilling • Longer laterals yield more production – to a point → cost considerations • Stage intervals • Number of intervals varies by shale play – most 300 to 400 ft • Most often, shorter intervals increase SRV and production → more cost • Couple with perforation interval distribution for optimum SRV from frac • Well Spacing

16. Perforation clusters • Typically evenly spaced along stage interval – good rock or bad • Number of clusters varies by shale play, less perm & complexity→ closer • Number of perfs affect limited entry diversion • The more clusters placed, the less contribute to production • Placement in better rock (fracs, brittle) may enhance SRV and production

17. Shale Fracture CharacteristicsDefinition of Brittleness from Rock Mechanics SPE 115258 Haynesville Eagle Ford Marcellus Woodford Barnett 70.00 56.00 42.00 28.00 14.00 00.00 BRIT

18. Barnett – example pump schedule • 4000 ft laterals • Span = ± 400 ft • Stage size = 15,500 bbl/stage • Prop volume = 4300 sks/stage • Number of stages 6 → 8 • Prop type: 60% 100 mesh, 40% 40/70 • Rate = 70 BPM • End sand conc= 1.25 – 1.5 ppg • Treating pressure = 4000 psi • SRV (ft3)= 4/3*π*ABC • A=network width • B=fraclength • C=height/2

19. Formation hardness and proppant embedment

20. Haynesville - example pump schedule

21. Simultaneous fracturing results • Simulfrac or Zipperfrac • Typically more microseismic activity • Overlapping microseismic behavior • Still see general fracturing behavior SPE 119896 (Rimrock)

22. Barnett - refrac potential Barnett Shale: Refrac – Water Frac Barnett Shale: Gel Frac Gel Frac Water Frac SPE 115771

23. Marcellus - more height growth & planar vs. Barnett • Experiment • Litefrac • 3000 ft lateral • 6 stages • 550,000 gal/stg • 97 bpm rate • 100,000 lb/stg • Slickwater • Typical • More planar than Barnett • Complexity • More stages • More perf clusters Barnett SPE 131783 Range Resources Corp

24. Haynesville - significant height growth • Haynesville • GMX fracture treatment • 3,000 – 5,000 ft laterals • 7 – 10 stages • 300 ft spacing • 2 perf clusters/stage • Stimulation • 300 to 500 K gal/stage • 65 bpmrate • 270,000 lb proppant/stage • Slickwater, hybrid, & X-link SPE 12507 GMX Resources

25. Woodford - containment • Fracture Lengths • Stage 1: 2500’ • Stage 2: 3300’ • Stage 2 RF: 1400’ • Stage 4: 1200’ • Fracture Heights • Stage 1: 250’ • Stage 2: 280’ • Stage 2 RF: 280’ • Stage 4: 280’ • Well contained SPE 110029 Antero

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27. Marcellus shale – frac height vsaquifer depth

28. Thank You