1. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 1/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

2. Slide — 2/35 Project Overview: ● Production Analysis Workflow  Data Correlation Verification  Preliminary Time-Rate Diagnostics  Time-Rate Relation Models ● 30-Year Cumulative Production Forecast ● Summary & Conclusions ● Ongoing & Future Work Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

3. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Production Analysis Workflow Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 3/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

4. Slide — 4/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Model Based Analysis Exponential & Hyperbolic Relations Semi-Analytical Rate-Cumulative Techniques Flowing Material Balance Preliminary Time-Rate Diagnostics Review & Edit Production DataIdentify Flow Regime(s) Data Correlation Verification Required Data Production DataWell HistoryReservoir and PVT Data Source: Ilk [2010]

5. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Production Data & Data Correlation Verification Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 5/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

6. Slide — 6/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

7. Slide — 7/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Well Cleanup Effects? Transient Responses Inaccurate Data Acquisition?

8. Slide — 8/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

9. Slide — 9/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Well Cleanup Effects? Transient Responses Inaccurate Data Acquisition?

10. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Editing Production Data Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 10/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

11. Slide — 11/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

12. Slide — 12/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

13. Slide — 13/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

14. Slide — 14/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

15. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Preliminary Time-Rate Diagnostics Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 15/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

16. Slide — 16/35 1:4 Slope (low F cD ) 1:2 Slope (high F cD ) 1:1 Slope Depletion Compound Linear Flow Regime Formation Linear Flow Regime Bilinear Flow Regime Elliptical Flow Regime Production Time Production Rate Transition Regime Time-Rate: Multi-Fracture Horizontal Well Flow Regimes Source: Blasingame [2011] Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

17. Slide — 17/35 Diagnostic Time-Rate Functions: Source(s):- Arps [1945, 1956] - Ilk et al. [2008] Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

18. Slide — 18/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Identify Flow Regime(s): 1:2 Slope (Linear) 1:1 Slope (Depletion)

19. Slide — 19/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Identify Flow Regime(s): 1:2 Slope (Linear)

20. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Model Based Exponential & Hyperbolic Time-Rate Relations Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 20/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

21. Slide — 21/35 Modified Hyperbolic Decline: Source(s):- Arps [1945, 1956] - Robertson [1988] Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

22. Slide — 22/35 Stretched Exponential Decline: Source: Valk ό. [2009] Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

23. Slide — 23/35 Power-Law Exponential Decline: Source: Ilk et al. [2008] Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

24. Slide — 24/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

25. Slide — 25/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

26. Slide — 26/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

27. Slide — 27/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

28. Slide — 28/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

29. Slide — 29/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

30. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations 30-Year Cumulative Production Forecast Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 30/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

31. Modified Hyperbolic (BSCF) Power-Law Exponential (BSCF) Stretched Exponential (BSCF) 2.712.442.38 Slide — 31/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

32. Modified Hyperbolic (BSCF) Power-Law Exponential (BSCF) Stretched Exponential (BSCF) 6.423.524.04 Slide — 32/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

33. Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Summary & Conclusions Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 33/35 Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

34. Slide — 34/35 ● Rate-Time Analysis Workflow  Edit production data to remove production noise and irregularities.  Calculate the diagnostic D(t), b(t), and β(t) functions.  Select the appropriate decline curve models based on the general trends of the data diagnostic functions.  Generate decline curve model solutions for q(t), D(t), b(t), and β(t) functions.  Plot [log-log] the well’s production and diagnostic functions along with the model solutions for visual inspection. ● Decline Curve Models  Understand the well’s flow regimes. What is the current flow regime? When will BDF occur?  Realize the assumptions inherent to the models.  Sensitive to noise and irregularities in production data.  Large variability in the 30-year EUR estimate between models. Modified Hyperbolic is typically the highest EUR estimate. Power-Law Exponential is typically the lowest EUR estimate. Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015)

35. Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Production Analysis of Eagle Ford Shale Gas Wells using Time-Rate Relations Avery Davis — Texas A&M University (8 February 2015) Evaluation & Workflow of Eagle Ford Shale Gas Wells using Time-Rate Relations End of Presentation Avery DAVIS Department of Petroleum Engineering Texas A&M University College Station, TX 77843-3116 (USA) Presentation for Directed Studies (PETE 685) College Station, TX (USA) — 8 February 2015 Slide — 35/35