Ditch samples from AP-4, ER-51 and UK-2 offshore Niger Delta were subjected to biostratigraphic and organic geochemical analyses which entail foraminiferal, palynological, Spore Colour Index (SCI), Rock-Eval Pyrolysis and Fourier Transform Infrared Spectroscopy (FTIR) analyses. The results have established N19 and N17; N17, N16 and N15; and N9 and N8 biozones; and P600 and P700 palynological zones. The dominance of palynomaceral (PM) I and II suggests Type III kerogen. PM III and IV (Type II and IV) were recorded. SCI ranges from 3/4 to 5/6 suggesting an early to mature liquid hydrocarbon generation phase. Rock-Eval Pyrolysis shows that the Total Organic Carbon (TOC), Hydrogen Index (HI), Pyrolysis temperature (T max ), and Vitrinite Reflectance (VR o ) range from 2.48 wt% - 6.37 wt%, 78 - 258, 411 ° C - 431 ° C and 0.26% - 0.69% respectively suggesting high TOC of Type II/III kerogen. FTIR indices show Type I kerogen in all the wells. VRo results range from 0.4 - 0.5 indicating an immature source. High concentrations of aliphatic saturates in identified functional groups indicate a low biodegradation. The abundance and diversity of recovered assemblages and dominance of PM I and II suggest shallow depositional environments with an age range of late Miocene to early Pliocene. Palynomaceral, SCI, and Rock-Eval inference contradict FTIR kerogen type suggesting that IR spectroscopy might not be suitable for kerogen typing and origin. The geochemical and biostratigraphical inferences must be corroborated for a successful evaluation. However, the source rock in the study area has adequate organic matter with the prospect to generate both oil and gas at appropriate maturity.
Combaz, A. (1964) Les palynofaciès. Revue de Micropaléontologie, 7, 205-218.
Ekweozor, C.M., Okogun, J.I., Ekong, D.E.U. and Maxwell, J.R. (1979) Preliminary Organic Geochemical Studies of Samples from the Niger Delta (Nigeria) I. Analyses of Crude Oils for Triterpanes. Chemical Geology, 27, 11-28. https://doi.org/10.1016/0009-2541(79)90100-1
Doust, H. and Omatsola, E. (1990) Niger Delta. In: Edwards, J.D. and Santogrossi, P.A., Eds., Divergent/Passive Margin Basins, American Association of Petroleum Geologists, Tulsa, 201-238. https://doi.org/10.1306/M48508C4
Eglinton, G. and Murphy, M.T.J. (1969) Organic Geochemistry: Methods and Results. Springer, Berlin, 838 p. https://doi.org/10.1007/978-3-642-87734-6
Hunt, J.M. (1996) Petroleum Geochemistry and Geology. 2nd Edition, Freeman, San Francisco.
Martinelli, G. (2009) Petroleum Geochemistry. In: Mesini, E. and Macini, P., Eds., Petroleum Engineering-Uptream, Encyclopedia of life Support Systems (EOLSS), Developed under the Auspices of the UNESCO, Eolss Publishers, Oxford, 193-216.
Reijers, T.J.A., Petters, S.W. and Nwajide, C.S. (1997) The Niger Delta Basin. In: Selley, R.C., Ed., African Basins. Sedimentary Basins of the World, Vol. 3, Elsevier, Amsterdam, 145-168. https://doi.org/10.1016/S1874-5997(97)80010-X
Knox, G.J. and Omatsola, E.M. (1989) Development of the Cenozoic Niger Delta in Terms of the ‘Escalator Regression’ Model and Impact on Hydrocarbon Distribution. In: van der Linden, W.J.M., Cloetingh, S.A.P.L., Kaasschieter, J.P.K., van de Graaff, W.J.E., Vandenberghe, J. and van der Gun, J.A.M., Eds., Coastal Lowlands, Springer, Dordrecht, 181-202. https://doi.org/10.1007/978-94-017-1064-0_12
Burke, K.C., Dessauvagie, T.F.J. and Whiteman, A.J. (1971) Opening of the Gulf of Guinea and Geological History of the Benue Depression and Niger Delta. Nature Physical Science, 233, 51-55. https://doi.org/10.1038/physci233051a0
Tuttle, M.L., Charpentier, R.R. and Brownfield, M.E. (1999) The Niger Delta Petroleum System: Niger Delta Province, Nigeria Cameroon, and Equatorial Guinea, Africa. United States Geological Survey, Reston, 4-35.
Reijers, T.J.A. (2011) Stratigraphy and Sedimentology of the Niger Delta. Geologos, 17, 133-162. https://doi.org/10.2478/v10118-011-0008-3
Short, K.C. and Stauble, A.J. (1967) Outline of the Geology of Niger Delta. American Association of Petroleum Geologists Bulletin, 51, 761-779. https://doi.org/10.1306/5D25C0CF-16C1-11D7-8645000102C1865D
Avbovbo, A.A. (1978) Tertiary Lithostratigraphy of Niger Delta: GEOLOGIC NOTES. American Association of Petroleum Geologists Bulletin, 62, 295-300. https://doi.org/10.1306/C1EA482E-16C9-11D7-8645000102C1865D
Kulke, H. (1995) Nigeria. In: Kulke, H., Ed., Regional Petroleum Geology of the World. Part II: Africa, America, Australia and Antarctica, Gebrüder Borntraeger, Berlin, 143-172.
Shannon, P.M. and Naylor N. (1989) Petroleum Basin Studies. Graham and Trotman Limited, London, 153-169.
Germeraad, J.H., Hopping, C.A. and Muller, J. (1968) Palynology of Tertiary Sediments from Tropical Areas. Review of Paleobotany and Palynology, 6, 189-348. https://doi.org/10.1016/0034-6667(68)90051-1
Evamy, B.D., Haremboure, J., Kamerling, P., Knaap, F.A., Molloy, F.A. and Rowland, P.H. (1978) Hydrocarbon Habitat of Tertiary Niger Delta. American Association of Petroleum Geologists Bulletin, 62, 1-39. https://doi.org/10.1306/C1EA47ED-16C9-11D7-8645000102C1865D
Tissot, B.P. and Welte. D.H. (1978) Petroleum Formation and Occurrence: A New Approach to Oil and Gas Exploration. Springer, Berlin, 538 p. https://doi.org/10.1007/978-3-642-96446-6
Batten, D.J. (1982) Palynofacies, Palaeoenvironments and Petroleum. Journal of Micropalaeontology, 1, 107-114, https://doi.org/10.1144/jm.1.1.107
Batten, D.J. (1996) Palynofacies and Palaeoenvironmental Interpretation. In: Jansonius, J. and McGregor, D.C., Eds., Palynology: Principles and Applications, Vol. 3, American Association of Stratigraphic Palynologists Foundation, College Station, 1011-1064.
Tyson, R.V. (1995) Sedimentary Organic Matter: Organic Facies and Palynofacies. Chapman and Hall, London, 615 p.
Fisher, M.J. (1980) Kerogen Distribution and Depositional Environments in the Middle Jurassic of Yorkshire, UK. Proceedings of the 4th International Palynological Conference, Lucknow (1976-77) 2, 574-580.
Phleger, F.B. (1960) Ecology and Distribution of Recent Foraminifera. The John Hopkins Press, Baltimore, 297 p.
Bandy, O.L. (1967) Relationships of Neogene Planktic Foraminifera to Paleoceanography and Correlation. Proc. 1st Intern. Conf. Planktic Microfossils, E.J. Brill, Leiden, 46-57.
Adegoke, O.S. and Stanley, D.J. (1972) Mica and Shells as Indicator of Energy Level and Depositional Regime on the Nigerian Shelf. Marine Geology, 13, M61-M66. https://doi.org/10.1016/0025-3227(72)90010-2
Adegoke, O.S., Omatsola, M.E. and Salami, M.B. (1976) Benthic Foraminifera Biofacies, off the Niger Delta. Maritime Sediments Special Publication, 1, 279-292.
Van Morkhoven, F.P.C.M., Berggren, W.A. and Edwards, A. S. (1986) Cenozoic Cosmopolitan Deep-Water Benthic Foraminifera. B Cent RechExpl, 11, 421.
Murray, J.W. (1991) Ecology and Palaeoecology of Benthic Foraminifera. Longman Group Limited, Harlow, 397.
Ibrahim, M.I.A., Al-Saad, H. and Kholeif, S.E. (2002) Chronostratigraphy, Palynofacies, Source-Rock Potential, and Organic Thermal Maturity of Jurassic Rocks from Qatar. GeoArabia, 7, 675-696. https://doi.org/10.2113/geoarabia0704675
Tyson, R.V. (1989) The Genesis and Palynofacies Characteristics of Marine Petroleum Source Rocks. In: Brooks, J. and Fleet, A.J., Eds., Marine Petroleumsource rocks, Geological Society Special Publication, Vol. 26, Geological Society, London, 47-67. https://doi.org/10.1144/GSL.SP.1987.026.01.03
Kholeif, S.E.H. and Ibrahim, M.I. (2010) Palynofacies Analysis of Inner Continental Shelf and Middle Slope Sediments Offshore Egypt, South-Eastern Mediterranean. Geobios, 43, 333-347. https://doi.org/10.1016/j.geobios.2009.10.006
Tissot, B.P. and Welte, D.H. (1984) Diagenesis, Catagenesis and Metagenesis of Organic Matter. In: Petroleum Formation and Occurrence, Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-87813-8_6
Ronov, A.B. (1958) Organic Carbon in Sedimentary Rocks (in Relation to Presence of Petroleum). Geochemistry (a Translation of Geokhimiya), No. 5, 510-536.
Dow, W.G. and O’Connor, D.E. (1982) Kerogen Maturity and Type by Reflected Light Microscopy Applied to Petroleum Exploration. In: Staplin, F.L., Dow, W.G., Milner, C.W.D., O‘Connor, D.I., Pocock, S.A.J., van Gijzel, P., Welte, D.H. and Yukler, M.A., Eds., How to Assess Maturation and Paleotemperatures, Society of Economic Paleontologists and Mineralogists, Tulsa, 133-157.
Peters, K.E. and Cassa, M.R. (1994) Applied Source Rock Geochemistry. In: Magoon, L.B. and Dow, W.G., Eds., The Petroleum System. From Source to Trap, American Association of Petroleum Geologists, Tulsa, 93-117. https://doi.org/10.1306/M60585C5
Jarvie, D.M., Claxton, B.L., Henk, F. and Breyer, J.T. (2001) Oil and Shale Gas from the Barnett Shale, Fort Worth Basin, Texas. American Association of Petroleum Geologists Bulletin, 85, A100.
Peters K. (1986) Guidelines for Evaluating Petroleum Source Rock Using Programmed Pyrolysis. American Association of Petroleum Geologists Bulletin, 70, 318-329. https://doi.org/10.1306/94885688-1704-11D7-8645000102C1865D
Espitalie, J., Devoo, G. and Marquis, F. (1982) La pyrolyse Rock-Eval et ses applications. Revue de l’Institut Francais du Pétrole, 40, 563-579. https://doi.org/10.2516/ogst:1985035
Hunt, J.M. (1979) Petroleum Geochemistry and Geology. W.H. Freeman, San Francisco, 617 p.
Barker, C. (1974) Pyrolysis Techniques for Source-Rock Evaluation. American Association of Petroleum Geologists Bulletin, 58, 2349-2361. https://doi.org/10.1306/83D91BAF-16C7-11D7-8645000102C1865D
Snowdon, L.R. (1989) Organic Matter Properties and Thermal Evolution. In: Hutcheon, I.E., Ed., Short Course I Burial Diagenesis, Mineralogical Association of Canada, Short Course Handbook, Vol. 15, Mineralogical Association of Canada, Toronto, 39-40.
Jackson, H.R., Forsyth, D.A. and Johnson, G.L. (1986) Oceanic Affinities of the Alpha Ridge, Artic Ocean. Marine Geology, 73, 237-261. https://doi.org/10.1016/0025-3227(86)90017-4
Peters K.E. and Moldowan J.M. (1993) The Biomarker Guide: Interpreting Molecular Fossils in Petroleum and Ancient Sediments. Prentice Hall, Englewood.
Miles, J.A. (1989) Illustrated Glossary of Petroleum Geochemistry. Oxford Science Publication, Oxford University Press, New York, 137 p.
Ganz, H. (1989) Die bedeeutung der infrarot-analysis fuer die kohlenwasserstoff-exploration. Habilitationsschrift der TU berlin.
Ganz, H. and Kalkreuth, W. (1987) Application of Infrared Spectroscopy to the Classification of Kerogentypes and the Evaluation of Source Rock and Oil Shale Potentials. Fuel, 66, 708-711. https://doi.org/10.1016/0016-2361(87)90285-7
Meredith, W., Kelland, S.-J. and Jones, D.M. (2000) Influences of Biodegradation on Crude Oil Acidity and Carboxylic Acid Composition. Organic Geochemistry, 31, 1059-1073. https://doi.org/10.1016/S0146-6380(00)00136-4
Larter, S.R., Huang, H., Adams, J., Bennett B., Jokanola, O., Oldenburg, T., et al. (2006) The Controls on The Composition of Biodegraded Oils in The Deep Subsurface: Part II-Geological Controls on Subsurface Biodegradation Fluxes and Constraints on Reservoir-Fluid Property Prediction. American Association of Petroleum Geologists Bulletin, 90, 921-938. https://doi.org/10.1306/01270605130