1. Moving Permian Basin Technology to the Gulf Coast: The Distribution of CO 2 EOR Potential in Gulf Coast Reservoirs Mark H. Holtz, Vanessa Núñez López, and Caroline L. Breton, Derik Woods, Shrivatsan Lakashminisharihan Development of a CO 2 Market in the Gulf Coast

2. Outline Technical inputs for market study  Residual oil saturation “is there a target”  CO 2 EOR Recovery “ can we get it”  Summary of published literature  BEG simulation studies, Dimensionless quick look screening model and full 3D Delineating the market  Development database  Devised a screening scheme  Determined algorithms for calculating EOR resource potential and CO2 Storage Market development: –First contact with Gulf Coast oil operators Summary Bureau of Economic Geology

3. Residency of CO 2 in an EOR Flood CO 2 dissolved in water CO 2 dissolved in residual oil CO 2 as separate residual phase CO2 CO 2 dissolved in produced oil Rock Grain

4. Formation of Residual Saturation Moore and Slobod, 1956 –Pore Doublet model Capillary force holds nonwetting phase in larger pore

5. Formation of Residual Saturation Oh and Slattery, 1976 –Snap-off model Capillary force cause nonwetting phase to snap-off into pore Aspect ratio = Pore radius Pore throat radius

6. Reported Residual Oil Saturation in Gulf Coast CO 2 EOR Pilots Reservoir Quarantine Bay Timbalier Bay Weeks Island Port Neches Little Creek Bay St. Elaine Paradis Residual oil to water (fraction) 0.38 0.29 0.22 0.3 0.21 0.1 to 0.4 0.26 Bureau of Economic Geology

7. Development of a Non-wetting Phase Saturation Prediction Method y = -0.3136Ln(x) - 0.1334 R 2 = 0.8536 0 0.2 0.4 0.6 0.8 1 00.10.20.30.40.50.6 Porosity (fraction) Residual non-wetting phase saturation (fraction) Gas Residual saturation to water (fraction) Frio Barrier bar Log. (Gas Residual saturation to water (fraction)) N = 143 Frio (Port Neches field) Bureau of Economic Geology

8. Recovery Efficiencies of Gulf Coast Sandstone CO 2 EOR Pilots CompanyReservoirFlood type Recovery factor (% of OOIP) TexacoParadis Miscible Gravity Stable15 Gulf/ChevronQuarantine BayWAG17 ChevronTimbalier BayGravity stable23 ShellWeeks Island S ReservoirGravity stable15 DenburyLittle CreekMiscible CO 2 17 Bureau of Economic Geology

9. Outline Technical inputs for market study  Residual oil saturation “is there a target”  CO 2 EOR Recovery “ can we get it”  Summary of published literature  BEG simulation studies, Dimensionless quick look screening model and full 3D Delineating the market  Development database  Devised a screening scheme  Determined algorithms for calculating EOR resource potential and CO2 Storage Market development: –First contact with Gulf Coast oil operators Summary Bureau of Economic Geology

10. GCCC Simulation Studies Quick Look Dimensionless Recovery Model GEM Simulator – 2D model Bureau of Economic Geology Innovative method for increasing reliability of CO 2 usage and CO 2 EOR volumetrics honoring reservoir data Derek Woods, GCCC student and Dr. Larry Lake, UT PE

11. Simulation Groups from Varying Reservoir Parameters Bureau of Economic Geology

12. Simulation Results Predict Oil Recovery per Volume CO 2 Injected Bureau of Economic Geology Pore volumes of CO 2 injected,

13. GCCC Reservoir Simulation Gillock Frio example Frio barrier strandplain sandstone, strucuraly complex Research questions –how much CO 2 for a two well test? What is the total volume recoverable and CO 2 use for this field? Bureau of Economic Geology

14. Outline Technical inputs for market study  Residual oil saturation “is there a target”  CO 2 EOR Recovery “ can we get it”  Summary of published literature  BEG simulation studies, Dimensionless quick look screening model and full 3D Delineating the market  Development database  Devised a screening scheme  Determined algorithms for calculating EOR resource potential and CO2 Storage Market development: –First contact with Gulf Coast oil operators Summary Bureau of Economic Geology

15. Methodology Data Development Sources of Data Texas: Atlas of Major Texas Oil Reservoirs, Atlas of Major Texas Gas Reservoirs, Railroad Commission of Texas, others Louisiana : TORIS database, Louisiana Geological Survey Alabama and Mississippi : Alabama Geologic Survey as a part of SECARB Bureau of Economic Geology

16. Decision Flow Path for Play Determination Postdepositional Physochemical Events Postdepositional diagenesis Tectonic overprint Geologic Province & Sub Province Geologic Stratigraphy Depositional System Geologic Play LithologyTrap Type Hydrocarbon & Drive Type Bureau of Economic Geology

17. Methodology Bureau of Economic Geology Oil-reservoir database Has reservoir been waterflooded? Minimum miscibility pressure (depth, temp., pressure, oil character) Does reservoir have water- drive mechanism? No Rejected No Rejected No Rejected No Yes Unknown Yes No Candidate reservoirs Candidate for secondary recovery Reservoir depth > 6000 ft Cumulative production > 1 MMSTB Yes DECISION TREE FOR SCREENING CANDIDATE RESERVOIRS

18. Screening Oil Reservoirs: Determine the Miscible CO 2 EOR Candidates Bureau of Economic Geology

19. Areas with Miscible CO 2 EOR Potential Bureau of Economic Geology

20. Miscible CO 2 EOR Resource Potential in the Gulf Coast Bureau of Economic Geology By State

21. CO 2 Sequestration Capacity in Miscible Oil Reservoirs along the Gulf Coast Bureau of Economic Geology

22. Oil Price Quality Correction West Texas Intermediate price used as a basis for comparison for Gulf Coast oil prices Data Base contains 5 years of monthly data with WTI prices, API gravities, and Gulf Coast operators oil prices Developed algorithm to calculate the oil price per reservoir in our database as a funtion of WTI and API Bureau of Economic Geology

23. Outline Technical inputs for market study  Residual oil saturation “is there a target”  CO 2 EOR Recovery “ can we get it”  Summary of published literature  BEG simulation studies, Dimensionless quick look screening model and full 3D Delineating the market  Development database  Devised a screening scheme  Determined algorithms for calculating EOR resource potential and CO2 Storage Market development: –First contact with Gulf Coast oil operators Summary Bureau of Economic Geology

24. Market Development; Operator Contact WTGS presentation: Moving Permian Basin Technology to the Gulf Coast: the Geologic Distribution of CO 2 EOR Potential in Gulf Coast Reservoirs Phone calls and email Site visits Seminar: Reserve Growth Potential from CO 2 Enhanced Oil Recovery Along the Gulf Coast –Emailed to PTTC contact list –Flyers handed out at SPE Galveston and Midland CO 2 conferences –Posted on PTTC and BEG web sites Bureau of Economic Geology

25. Over 40 participants 34 companies

26. Summary Technical innovations have been developed A large potential for reserve growth lies along the Gulf Coast through the application of CO 2 miscible enhanced oil recovery. Results indicate that there is the potential for approximately 4.7 BSTB of addition oil reserves. Texas contains the greatest oil CO 2 EOR potential with a target of over 3 BSTB. The largest resource lies in Frio Formation; – Barrier/Strandplain Sandstones, – Frio Fluvial/Deltaic Sandstones, – Frio Deep-Seated Salt Domes Numerous operators believe CO 2 EOR could add reserves to their Gulf Coast assets. Bureau of Economic Geology