1. Applying Fluid Inclusions to Petroleum Exploration and Production

2. Main Points u Fluid inclusion techniques are flexible tools applicable to fundamental E&P problems u These techniques can increase our understanding of the petroleum system and help manage E&P risk by assessing the present and past distribution of petroleum, its sources and characteristics u Fluid Inclusion Stratigraphy (FIS) can help high-grade present and future prospects

3. What are Fluid Inclusions? u Micron-scale, fluid-filled isolated cavities in or between crystals in rock material u Form during subsurface diagenetic process in which mineral cement is added to intergranular pore space or microfractures u Are representative of past or near-present- day pore fluids. They track movement of aqueous and petroleum fluids

4. Fluid Inclusions in Sandstone

5. Petroleum Inclusion in Quartz

7. Why Care About Fluid Inclusions? u May be the freshest samples of reservoir fluids we have u Remain even after pore fluids change (applications for fossil migration paths, flushed reservoirs and tilted oil-water contacts) u Record multiple charges, temperatures and pressures

8. Classical Approach u Thin section based u Assumes selection of the most relevant samples for analysis u Best applications are for P-T-X assessment; petroleum compositions typically are crudely constrained, or inferred by local production u Difficult to apply to dry gas problems u Regional evaluations are time-intensive

9. Fluid Inclusion Stratigraphy (FIS) u Stratigraphic mapping of paleofluid chemistries through bulk mass spectrometric analysis of fluid inclusion volatile species (inorganics and organics to C13) u Rapid, automated analytical system allows cost-effective, regional evaluation of thousands of samples in a matter of days

10. Schematic of FIS Technique

11. Depth plots of critical species and compound ratios integrated with electric logs indicate petroleum inclusion distribu- tion seals and proximal pay FIS Data

12. E&P Applications of FIS u Mapping migration pathways u Pay delineation / relative fluid saturation / oil-water and gas-water contacts u Implying up-dip pay from wet wells u Implying deeper prospectivity from shallow drilling u Product type and quality issues (sour gas, biodegradation, oil vs. gas)

13. E&P Applications of FIS (Cont.) u Reservoir connectivity u Seal identification and effectiveness u Pressure compartments u Identifying products evolved from mature source rocks u Fault location u Exposure surface delineation

14. Inferring Up-Dip Prospectivity from a Wet Well u Well drilled off structure with no shows; reservoir sand was wet u Strong FIS liquid and gaseous petroleum indications were obtained on wet reservoir sand, suggesting that oil and gas migrated through target section u Up-dip well discovered oil and gas in reservoir equivalent interval; API matched that measured in thin section on wet well

15. Up-dip Prospectivity from Wet Well

16. Local Prospectivity / Deeper Potential from Shallow Drilling u FIS data from rich gas-condensate discovery delineates top of pay and regional seal u Shallow leakage of gas and liquids is encouraging for deeper potential u FIS data from dry hole in same basin does not show evidence of shallow seep signature nor migration through reservoir section

17. Local Prospectivity / Deeper Potential

18. Pay Delineation u Excellent top seal to gas reservoir u Gas column delineated; chemistries track porosity u Present-day gas-water contact defined u TSR products identified; moderately sour gas is indicated u Interpretations verified with production tests

19. Pay and Product Definition

20. Monitoring Extent of TSR in Fluid Inclusions u Progressive decrease in higher molecular weight organic species (e.g., C7-C13) and alkanes in general u Progressive increase in TSR products: H2S, CO2 u Progressive increase in TSR intermediaries: Sulfur species (COS, CS2, S2), organic acids, simple aromatics

21. C 7 Alkane/Benzene H 2 S / CH 4 Progressive TSR Extent of TSR from Fluid Inclusions

22. Percent H 2 S A Fluid Inclusions Produced Gas 0 50 100 B C D H 2 S Prediction from Fluid Inclusions

23. EOR Application in a Mature Field u Depth of original oil-water contact needed for waterflood planning u Original contact was disturbed by production u Wells were incrementally deepened over the history of field; log suites are minimal u FIS data indicate the position of the OWC

24. EOR Application

25. Regional Evaluation u 20,000 samples from 180 wells evaluated with FIS in 6 weeks u Defined areas of gas, condensate and oil prospectivity u Suggested deeper potential in areas with shallow well control. u Basin-scale high-grading tool

26. Plan View Constant Depth 60,000 sq. km. 180 Wells 24,000 Samples FIS for Regional Evaluation

27. Identifying Seals u FIS methane distribution for several wells along transect document low abundance across regional seal u Additional FIS data indicate that fluid on either side of seal has discrete chemistry, suggesting limited communication over geologic time u Geochemical data suggest reservoirs pro- duce petroleum from different source rocks

28. Seal Definition / Characterization

29. Proximity-to-Pay Concept

30. Inferring Nearby Undrilled Pay u Well through center of prospect encountered no reservoir; had no shows u Cuttings document anomalous levels of benzene, toluene and organic acids in the reservoir equivalent section (the lateral seal) u Subsequent drilling discovered field u Geochemical halo effect can be used to enlarge exploration target

31. FIS Infers Nearby Undrilled Pay

32. FIS “Proximity” Geometries

33. Follow-Up Analyses: Tools u Petrography u Microthermometry u API gravity determination u Crush-GC u TE or SE-GCMS u Isotopic Analysis u Confocal SLM

34. Follow-Up Analyses: Information u Timing u Temperature u Pressure u Composition u Source u Maturity u Origin

35. Mature, Carbonate Source Rock Calcite Vein Liquid Petroleum Inclusions and Solid Bitumen Inclusions Petroleum Inclusions in Source Rock

36. Homogenization Behavior of Petroleum Inclusions

37. Reservoir Filling History from Fluid Inclusions

38. Paleo-Pressure and Temperature

39. Oil Inclusion API Gravity

40. Oil Inclusion API Gravity #2

41. Crush GC Data on Fluid Inclusions

42. GCMS Data From Fluid Inclusions

44. Biogenic vs. Thermogenic Gas in Fluid Inclusions

45. Prevailing Migration Model: Liuhua Area, Offshore China

46. Migration Model with Integration of FIS, GCMS and Isotope Data

47. Hydrothermal Experimentation: Simulating Basin Processes

48. Compaction Experiment: Phosphoria Shale and Sand 1:9

49. Cementation Experiment: Phosphoria Shale and Sand 1:9

52. Process for Fluid Inclusion Study 1

53. Process for Fluid Inclusion Study 2

54. Process for Fluid Inclusion Study 3

55. Summary u Fluid inclusion techniques are robust, and applicable to many fundamental E&P questions u Inclusion petroleum is unfractionated and unaltered by sampling or storage procedures. Applicable to oil-based muds u FIS allows rapid, regional evaluation of migration, seals and proximity to pay

56. Summary (Cont.) u Coupling FIS with petrophysical data improves reservoir evaluation u Coupling FIS with classical geochemical methods improves analysis of petroleum system and reservoir continuity u FIS and conventional fluid inclusion analyses constrain basin models