Figures index

From

Biomarker Geochemical Evaluation of Organic Rich Shales in Mamfe Basin, Cameroon

Edwin Ayuk Ndip, Christopher M. Agyingi, Matthew E. Nton, Michael A. Oladunjoye

Journal of Geosciences and Geomatics. 2021, 9(1), 28-44 doi:10.12691/jgg-9-1-4
  • Figure 1. Geologic map of the Mamfe region (modified after 18)
  • Figure 2. Representatives outcrops (a and b) and lithological log (c) of the Mamfe Formation
  • Figure 3a, b. A representative m/z 85 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 3c, d, e. A representative m/z 85 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 3 f, g. A representative m/z 85 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 4 a, b, c. A representative m/z 191 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 4 d, e, f, g. A representative m/z 191 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 5 a, b. A representative m/z 217 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 5 c, d, e, f. A representative m/z 217 mass chromatograms of saturated hydrocarbon fractions of the studied samples
  • Figure 6. Pr/Ph vs. CPI, indicating paleodepositional conditions of the studied samples (after 27)
  • Figure 7. Pristane/n-C17 vs. phytane/n-C18 for the investigated samples (after 8)
  • Figure 8. Hopane and isoprenoid ratios of organic matter extracts used to discriminate the depositional environments for Mamfe sediments (modified after 8)
  • Figure 9. Cross-plot of C26 (R+S) T/C25T versus C24Tet/C26(R+S) T showing increasing terrigenous input in the studied sediments (after 30)
  • Figure 10. Cross-plot of C23T/C24T versus C24Tet/C26T, also showing increasing terrigenous input in the studied samples (after 30)
  • Figure 11. Cross-plot of hopane/sterane ratios vs. Pr/Ph ratios (after 30)
  • Figure 12. Cross-plot of C27/ (C27+ C29) regular steranes versus Pr/Ph ratios showing paleodepositional conditions and source origin of the organic matter extracts of the studied sediments
  • Figure 13. Ternary plot showing the relationship between sterane composition and depositional environment (after 43)
  • Figure 14. Relationship between regular sterane compositions, organic matter origin, and depositional environment for the analysed Mamfe extracts (modified after 43)
  • Figure 15. Plots of n-alkanes showing interpretation of organic matter thermal maturity in the studied samples
  • Figure 16. Cross-plot of two biomarker parameters sensitive to thermal maturity for the studied samples, which shows that most of the Mamfe Formation samples plot in the area of early oil window maturity (after 7)