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Geoforensics for oil characterization WBPC2015

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Geoforensics for oil characterization WBPC2015

  1. 1. Making chemistry data meaningful Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Phil Richards and Court Sandau © 2015 Chemistry Matters Inc.
  2. 2. 2 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Origin of Madison oil? 7 samples of oil from 2 areas in Canadian WB: o  Area A – 2 Midale o  Area B – 2 Midale o  Area B – 3 Frobisher From: USGS 2010. Geological Assessment of Undiscovered Oil and Gas Resources in the Madison Group, Williston Basin, North Dakota and Montana
  3. 3. Origin of Madison oil? 3 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Madison Group (Lodgepole, Frobisher, Midale, Ratcliffe, Poplar) (Carbonate) Bakken Formation (Shale) From: Obermajer et al. 2000, Org. Geochem. 31, 959.
  4. 4. 4 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? o  Originally proposed that “Bakken shale” was the source of overlying oil reservoirs of the Madison Group. o  Later established that the “Madison carbonates” were the most probable source for the Madison Group. o  Variations within localized traps. o  Potential for localized mixing-in of Bakken oil. Origin of Madison oil? From: Obermajer et al. 2000, Org. Geochem. 31, 959.
  5. 5. 5 GC-MS © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? nC8 nC9 nC10 nC12 nC11 nC13 nC14 nC15 nC16 nC17 nC18 nC19 nC20 nC21 nC22 nC23 nC24 nC25 nC26 nC27 nC29 nC28 nC30 nC32 nC31 nC33 nC34 nC35 nC36 nC37 nC38 o  Alkanes o  Isoprenoids o  Alkylcyclohexanes o  Sesquiterpanes o  Adamantanes o  Alkylbenzenes o  PAHs o  Alkyl-PAHs o  Hetero-PAHs o  Steranes and Terpanes…
  6. 6. 2DGC-TOFMS 6 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Alkanes Bicyclic Alkanes Naphthalenes BT DBT PAHs Steranes Hopanes MAS TAS
  7. 7. Biomarkers 7 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Originate from complex biological molecules Membrane structural chemicals o  Terpanes – prokaryotes (archea and bacteria) o  Steranes – eukaryotes (plants and animals) Relative concentrations of biomarkers can provide information of the origin and history of the oil.
  8. 8. Biomarkers 8 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Typical Bakken Typical Lodgepole Example of Madison oil product Terpanes 1. Pattern of C21-C24 tricyclic terpanes 2. Ratio of Ts/Tm 3. Ratio of 17a21b-30-norhopane relative to 17a,21b-hopane 4. Enrichment of C35 homohopanes 1 2 31 2 31 2 3 4 4 4 From: Obermajer et al. 2000, Org. Geochem. 31, 959.
  9. 9. Biomarkers 9 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Typical Bakken Typical Lodgepole Example of Madison oil product Steranes f C27 oils, C27 ce of ining and pro- ed to Mol- rther mpo- tion ratios) as the majority of oils from this family have C21/C29 regular sterane ratio of less than 1.0. The epimerization ratios of C29 regular steranes are quite variable and inconclusive with respect to deter- mining maturity of oils. The C29 abb/(aaa+abb) reg- ular sterane isomerization ratio is the highest in oil families B and C, often approaching equilibrium values. Interestingly, this trend is not parallelled by the C29 S/(S+R) isomerization ratio which is the highest in oil families A and D. These variable ratios are not always consistent with maturity data derived from the gasoline range parameters and the distribution of n-alkanes and the saturate fraction showing the distribution of steranes in the Williston H) 20S- C27 diasterane, C29±C29 regular sterane. similar in all oil families, the proportion of C27 29 members is more variable. In the family B oils, 9 sterane occurs in same concentration as C27 e (Table 2). In contrast, the relative abundance of erane are increasingly greater in the remaining s, reaching more than 50% in oil families D and erage of 51% and 58%, respectively). The pro- n of C27:C28:C29 regular steranes is considered to ighly speci®c correlation index (Peters and Mol- , 1993, pp. 182±186), therefore providing further t for classifying studied oil samples into compo- ly distinct oil categories. tion ratios) as the majority of oils from this family have C21/C29 regular sterane ratio of less than 1.0. The epimerization ratios of C29 regular steranes are quite variable and inconclusive with respect to deter- mining maturity of oils. The C29 abb/(aaa+abb) reg- ular sterane isomerization ratio is the highest in oil families B and C, often approaching equilibrium values. Interestingly, this trend is not parallelled by the C29 S/(S+R) isomerization ratio which is the highest in oil families A and D. These variable ratios are not always consistent with maturity data derived from the gasoline range parameters and the distribution of n-alkanes and Representative m/z 217 mass fragmentograms of the saturate fraction showing the distribution of steranes in the Williston ils. C21- pregnane, C27dia-17(H), 13
  10. 10. (H), 17(H) 20S- C27 diasterane, C29±C29 regular sterane. C27 C28 C29 C27 C28 C29 Pattern of cholestanes (C27-C28-C29) From: Obermajer et al. 2000, Org. Geochem. 31, 959.
  11. 11. Isoprenoids 10 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Pristane (Pr) and Phytane (Ph) originate from the decomposition of chlorophyll oxidizing reducing
  12. 12. 0.0# 0.4# 0.8# 1.2# 1.6# 2.0# Sample# 1# Sample# 2# Sample# 3# Sample# 4# Sample# 5# Sample# 6# Sample# 7# Pr#/#Ph#Ra(o# Isoprenoids 11 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Pristane / Phytane ratio 1, conditions generally in line with Lodgepole (carbonate) source. Some differences (Sample 3 and 4) Bakken oils Lodgepole oils Pristane Phytane 0.0# 1.0# 2.0# 3.0# 4.0# 5.0# 6.0# 7.0# Midale# A1# Midale# A2# Midale# B3# Midale# B4# Frob##### B5# Frob#### B6# Frob#### B7# DBT$/$Phen$ra,o$
  13. 13. 0.0# 1.0# 2.0# 3.0# 4.0# 5.0# 6.0# 7.0# Midale# A1# Midale# A2# Midale# B3# Midale# B4# Frob##### B5# Frob#### B6# Frob#### B7# DBT$/$Phen$ra,o$ Other indicators (PAHs) 12 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Bakken oils Lodgepole oils DBT Phen High sulfur content of Lodgepole carbonates.
  14. 14. 0 0.4 0.8 1.2 1.6 2 Midale A1 Midale A2 Midale B3 Midale B4 Frob B5 Frob B6 Frob B7 Ts#/#Tm#ra(o# Other indicators (Terpanes) 13 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Ts Tm Bakken oils Lodgepole oils
  15. 15. More detailed analysis All 7 samples conform with general Lodgepole origin. •  Bakken Contributions •  Maturity •  In situ degradation 14 Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? © 2015 Chemistry Matters Inc.
  16. 16. 0.3$ 0.4$ 0.5$ 0.6$ 0.7$ 0.8$ 0.9$ 1.0$ 1.1$ 1.2$ 2.0$ 3.0$ 4.0$ 5.0$ 6.0$ 7.0$ Pr#/#Ph# DBT#/#Phen# Sample$1$ Sample$2$ Sample$3$ Sample$4$ Sample$5$ Sample$6$ Sample$7$ 15 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Dibenzothiophene Phenanthrene Pristane Phytane Potential For Bakken Contributions Bakken 0.15% 0.2% 0.25% 0.3% 0.35% 0.4% 0.6% 1.1% 1.6% 2.1% Ts#/#(Ts+Tm)# TAS#/#MAS# Midale%A1% Midale%A2% Midale%B3% Midale%B4% Frob%B5% Frob%B6% Frob%B7% M-B
  17. 17. 0.15% 0.2% 0.25% 0.3% 0.35% 0.4% 0.6% 1.1% 1.6% 2.1% Ts#/#(Ts+Tm)# TAS#/#MAS# Midale%A1% Midale%A2% Midale%B3% Midale%B4% Frob%B5% Frob%B6% Frob%B7% 16 Maturity Indicators © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Triaromatic Steranes Monoaromatic Steranes Ts Tm
  18. 18. 0.0# 0.5# 1.0# 1.5# 2.0# 2.5# 0.4# 0.6# 0.8# 1.0# n12$/$i13$ Pr$/$Ph$ Sample#1# Sample#2# Sample#3# Sample#4# Sample#5# Sample#6# Sample#7# Mixing and in-situ degradation 17 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? ‘Weathering’ M-A M-B F-B Frobisher samples present ‘in situ’ weathering - loss of light end straight-chain hydrocarbons Bakken 0.15% 0.2% 0.25% 0.3% 0.35% 0.4% 0.6% 1.1% 1.6% 2.1% Ts#/#(Ts+Tm)# TAS#/#MAS# Midale%A1% Midale%A2% Midale%B3% Midale%B4% Frob%B5% Frob%B6% Frob%B7%
  19. 19. In-situ degradation 18 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? Midale o  Normal profile of hydrocarbons Frobisher o  Altered profile •  Biodegradation •  Water / CO2 flood
  20. 20. Summary 19 © 2015 Chemistry Matters Inc. Geoforensic Chemical Analysis of Oil Samples from the Madison Group What Can It Tell Us? •  Standard geoforensic analysis Midale and Frobisher samples are of carbonate origin •  Detailed geoforensic analysis Midale samples demonstrate origin differences o  2 samples may present minor Bakken contributions o  1 sample presents distinctly higher maturity Frobisher samples present alteration o  ‘in situ’ biodegradation / washing
  21. 21. Thank You prichards@chemistry-matters.com www.chemistry-matters.com 403.478.3375

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