Earth, Energy & Environment
Received: 28 Apr 2018 , Published: 06 May 2018
Views: 69 , Download: 50
|1||Uzoegbu, M. U|
The thermal maturity parameter used in the evaluation of the hydrocarbon generative potential of the sedimentary organic matter is based largely on the extent of molecular transformation of the biological markers due to geothermal stress which is a function of depth or burial history. The shale samples were collected at Gbekebo ditch cutting locality. The samples were examined and analyzed to determine their oil and gas potential. The HI values range from 2.00 to 327.07 mgHC/gTOC with a mean value of 103.46 mgHC/gTOC indicates a Type III and mixed Type II/III kerogen. Tmax values ranging from 415 to 437 oC with an average of 429.50 oC shows that the shale samples are immature to marginally mature. The total organic carbon (TOC) (1.61 wt%) and S1 + S2 (2.81) of the shale constitutes that of a excellent source rock with gas-prone kerogen indicated by Rock-Eval S2/S3 (5.59). The high oxygen index (OI) (40.85 mgCO2g-1TOC) suggest deposition in a shallow marine environment. Biomarker analysis of the shale samples generally reveal a bimodal nalkane envelope with maxima between (nC16 and nC18) and (nC27 and nC29) suggesting that the source organic matter were derived from a variable mixture of algae and higher plant materials with q relative higher input from marine algae as reveal by the presence of the C30 24-n-propyl cholestane (%C30 sterane range from 0.45 to as high as 5.23%). The presence of organic matter of marine algae (%C27 sterane av. 52% and positive detection of C30 sedimentary n-propyl cholestane av. 3.7%) suggest that the control on the HI as an indication of source rock quality in varying level of organic matter preservation. The source rocks have predominantly gas prone with lesser oil prone organic matter ranging from immature to marginally mature at shallow levels but may reaching proven mature levels in the subsurface.
Adediran, S. A. and Adegoke, O. S. 1987. Evolution of the sedimentary basins of the Gulf of Guinea. In: Current Research in Africa Earth Sciences, Matheis and Schandeimeier (eds). Balkema, Rotterdam., p. 283-286.
Adegoke, O. S. 1969. Eocene stratigraphy of Southern Nigeria. Mem. Bur. Rech. Geol. mins., p. 23-46.
Adekeye, O.A. 2004. Aspects of sedimentology, geochemistry and hydrocarbon potentials of Cretaceous-Tertiary sediments in the Dahomey Basin, south-western Nigeria. Unpublished Ph.D thesis, University of Ilorin, 202p.
Adekeye, O. A. and Akande, S.O., (2010). The Principal Source Rocks for Petroleum Generation in the Dahomey Basin, Southwestern Nigeria. Continental J. Earth Sciences 5 (1): 42 – 55.
Adekeye, O.A., Akande, S.O., Erdtman, B.D., Samuel, O.J. and Hetenyi, M. 2006. Hydrocarbon Potential Assessment of the Upper Cretaceous-Lower Tertiary Sequence in the Dahomey Basin Southwestern Nigeria. NAPE Bulletin. v. 19 No 1, p.50-60.
Agagu OK, Ekweozor CM (1982). Source Rock Characteristics of Senonian in the Anambra Syncline, Southern Nigeria. J. Min. Geol.10: 132-140.
Akaegbobi IM, Schmitt M (1998). Organic Faces, Hydrocarbon Source Potential and Reconstruction of the Depositional Paleo Environment of the Campano-Maastrichtian Nkporo Shale in the Cretaceous Anambra Basin, Nigeria. Nigerian Association of Petroleum Explorationists, (NAPE), Bulletin, 13: 1-19.
Akande, S. O. and Erdtmann, B. D., 1998. Burial metamorphism (thermal maturation) in Cretaceous sediments of the Southern Benue Trough and Anambra Basin, Nigeria. AAPG Bulletin, 82(6), 1191-1206.
Akande, S.O., Ogunmoyero, I.B., Petersen, H.I. and Nytoft, H.P. 2007. Source rock evaluation of coals from the Lower Maastrichtian Mamu Formation, SE Nigeria. Jour. Petrol. Geol., 30(4), 303-324.
Ako, B. D., Adegoke, O. S. and Petters, S. W. 1980. Stratigraphy of the Oshosun Formation in South-Western Nigeria. Jour. Min. Geol. v. 17, p. 97-106.
Ameh, C., Aina, O., Ogbuwa, K., Abrakasa, S. and Ideozu, R. (2016), Source Rock Geochemistry of the Nsukka Formation in Arochukwu Area of Afikpo Basin, South?Eastern Nigeria. IOSR Journal of Applied Geology and Geophysics, 4(5), pp. 24-28.
Asmus, H. E. And Ponte, F. C. 1973. The Brazillian marginal basins: In: Naim, A. E. M and Stehli, F. G. (Eds).Ocean Basins and margins: The South Antlantic, The Plenum Press, v. 1, 250p.
Beka, F., Ukaegbu, V., Oluwajana, O., Oledinma, N., Njoku, I., Beka, J., Amaechi, L. and Udoh, M. 2007. Spatial profiling of shaly facies and palaeoenvironment reconstruction of gas prone sequences in the Anambra Basin, Nigeria. Nig. Assoc. Petrol. Expl. 25th Annual Conf., Abuja, Nigeria, 2007. Abs. Vol., 25p.
Billman, H. G. 1976. Offshore stratigraphy and paleontology of the Dahomey embayment. Proc. 7th Afri. Micropal. Coll. Ile-Ife, p. 27-42.
Bordenave, M.L., Espitalie, J., Leplat, P, Oudin, J.L. and Vandenbroucke, M. (1993). Screening techniques for source rock evaluation. In: Bordenave, M. L. (Eds.) – Applied Petroleum Geochemistry, Editions Technip, Paris, 217-278.
Bray, E.E. & Evans, E.D. 1961. Distribution of n-paraffins as a clue to recognition of source beds. Geochimica et Cosmochimica Acta, 22, p.2-5.
Cooles, G.P., Mackenzie, A.S., and Quigley, T.M.: (1986), Calculation of petroleum masses generated and expelled from source rocks. In: Leythaeuser, D., and Rullk?tter, J., (eds.), Advances in organic Geochemistry, Oxford, Pergamon, Organic Geochemistry, 10, 235-245
Didyk, B. M., Simoneit, B. R. T., Brassell, S. C. & Eglinton, G. 1978. Organic geochemical indicators of paleoenvironmental conditions of sedimentation. Nature, 272, p.216-222.
Eseme, E., Littke, R., Agyingi, C.M., 2006. Geochemical characterization of a Cretaceous black shale from Mamfe Basin, Cameroon. Petroleum Geosciences., 12, 69 – 74.
Espitalie, J., Marquis, F., and Barsony, I. 1985. Geochemical logging. In: Analytical Pyrolysis – Techniques and Applications, K. J. Voorhees (Ed.) Boston, Butterworth, 276-304.
Goodwin , T.W., 1973. Comparative Biochemistry of Sterols in Eukaryotic Micro-organisms. In: Erwin , J. A. (ed.), Lipids and Biomembranes of Eukaryotic Micro-organisms, Academic Press, New York, p. 1-40.
Hunt, J. M. 1996. Petroleum geochemistry and geology. 2nd Edition, Freeman and Co., New York.
Idowu, J. O., Ajiboye, S. A., Ilesanmi, M. A. and Tanimola, A. 1993. Origin and significance of organic matter of Oshosun Formation south-western Dahomey Basin Nigeria. Jour. Min. Geol. v. 29, p. 9-17.
Jovancicevic, B., Wehner, H., Scheeder, G., Stojanovic, K., Sainovic, A., Cvetkovic, O., Ercegovac, M. and Vitorovic, D. 2002., Search for source rocks of the crude oils of the Drmno deposition (southern part of the Pannonian Basin, Serbia). Jour. Serbian Chem. Soc., 67, 553 – 566.
Kogbe, C. A. 1974. Paleo-ecologic significance of vertebrate fossil in the Dukamaje and Dange Formations (Maastrichtian and Paleocene) of northwestern Nigeria. Jour. Min. Geol.(Nigeria). v. 8, p. 49-55.
Lafargue, E. Marquis, F. and Pillot, D. 1998. Rock- Eval 6 applications in hydrocarbon exploration, production, and soil contamination studies. Renue de L’ Inst. Fr. Petrole, 53(4), 421-437.
Langford, F. F. and Blanc- Valleron, M. M. 1990. Interpreting Rock-Eval pyrolysis data using graphs of pyrolyzable hydrocarbons vs Total Organic Carbon. Amer. Assoc. Petrol. Geol. Bull., 74(6), 799-804.
Lehner, P. and de Ruiter, P. A. C. 1977. Structural history of the Atlantic margin of Africa.AAPG Bull. v. 61, p.961-981.
Leythaeuser, D., Hagemann, H.W., Hollerbach, A. and Schaefer, R.G. 1980. Hydrocarbon generation in source beds as a function of type and maturation of their organic matter: a mass balance approach. Proc. World Petrol. Congr., 2, Heyden, 31-41.
McKenzie A.S. et al. (1987), The expulsion of petroleum from Kimmeridge Clay source-rocks in the area of the Brae oilfield, UK continental shelf, in: Petroleum geology of North West Europe. Proceedings of the 3rd conference on petroleum geology of North West Europe, London, 26-29 October, 865-877.
Mpanda, S. 1997. Geological development of East African coastal basin of Tanzania: Acta Universities Stockholmiensis, v. 45, 121p.
Nwajide CS (2005). Anambra basin of Nigeria: Synoptic basin analysis as a basis for evaluating its hydrocarbon prospectivity . In Okogbue, C. O (ed.) Hydrocarbon potentials of the Anambra basin; geology, geochemistry and geohistory perspectives. Great AP Express Publ., Ltd., Nsukka. pp.1 – 46.
Ogbe, F. A. G. 1970. Stratigraphy of strata exposed in the Ewekoro Quarry Western Nigeria. In:(Dessauvagie, T. F.J. and Whiteman, A. J. (eds). African Geology University of Ibadan Press, Nigeria. p.305-324.
Ojeda, H. A. 1982. Structural framework, stratigraphy, and evolution of Brazilian basins. AAPG Bull. v. 66, p.732-749.
Okosun, E. A. 1990. A review of the Cretaceous stratigraphy of the Dahomey Embayment, West Africa. -Cretaceous Research, v. 11, p. 17-27.
Omatsola, M. E. and Adegoke, O. S. 1981. Tectonic evolution and Cretaceous Stratigraphy of the Dahomey Basin. Jour. Min. Geol. v. 8, p. 30-137.
Peters, K.E. (1986). Guidelines for evaluating petroleum source rocks using programmed pyrolysis. AAPG Bulletin, 70, 318-329.
Pollastro, R. M. and Barker, C. E. 1986. Application of clay mineral, vitrinite reflectance and fluid inclusion studies to the thermal and burial history of the Pinedale anticline, Green River basin, Wyoming. SEPM Special Publication. v.28, p. 73-83.
Rullkötter, J., Leythaeuser, D., Horsfield, B., Littke, R., Mann, U., Müller, P. J., Radke, M., Schaefer, R. G., Schenk, H. J., Schwochau, K., Witte, E. G. And Welte, D. H. (1988), Organic matter maturation under the influence of a deep intrusive heat source: A natural experiment for quantitation of hydrocarbon generation and expulsion from a petroleum source rock (Toarcia Shale, northern Germany. In: Mattsvelli, L and Novelli, E (Eds.): Advances in Organic Geochemistry, 1987. Organic Geochemistry, 13, 847-856.
Storey, B. C. 1995. The role of mantle plumes in continental break up: case history from Gondwanaland – Nature, v. 377, p. 301-308.
Tissot, B. P. and Welte, D. H. 1978. Petroleum formation and occurrence., Springer-Verlag, New York, 538p.
Tissot, B. P. and Welte, D. H. 1984, Petroleum Formation and Occurrence, 2nd ed. Spinger Verlag, Berlin 699p.
Udofia, G. G. and Akaegbobi, I. M. 2007. Integrated geochemical and organic petrographic characterization of the Campano-Maastrichtian sediments around Enugu Escarpment, Anambra Basin, Southeastern Nigeria. Nig. Assoc. Petrol. Expl. 25th Annual Conf., Abuja, Nigeria, 2007. Abs. Vol., 22p.
Uzoegbu, M.U. and Ikwuagwu, C.S., 2016a. Hydrocarbon Generative Potential of Campanian Source Rock from Ihube, Anambra Basin, Nigeria. International Journal Geology and Mining, 2(1), 053-063.
Uzoegbu, M.U. and Ikwuagwu, C.S., 2016b. Characterization of Organic Matter and Hydrocarbon Potential of Shale from Uturu, Isigwuato, SE Nigeria. International Journal of
Scientific and Research Publications, 6(6), 754-759.
Volkman J.K. & Maxwell, J.R 1986. Acyclic isoprenoids as biological markers. In: Johns, R.B. (ed.) Biological markers in sedimentary record, Elsevier, New York, pp. 1-42.