Earth, Energy & Environment

Earth, Energy & Environment

BIOMARKER GEOCHEMICAL EVALUATION OF UPPER CRETACEOUS COAL FROM THE ANAMBRA BASIN, SOUTHEAST NIGERIA: IMPLICATION FOR PETROLEUM GENERATION.

Pages: 31  ,  Volume: 5  ,  Issue: 2 , May   2018
Received: 01 Jun 2018  ,  Published: 03 June 2018
Views: 74  ,  Download: 37

Authors

# Author Name
1 Uzoegbu, M.U., Agbo, C.C., Amoke, A.I. and Ikwuagwu, C.S.

Abstract

ABSTRACT

 

The abundance of hopanes, homohopanes (C31-C35), benzohopanes and C29 steranes and diasteranes in most of the samples indicate terrestrial plant, phytoplankton and cyanobacteria contributions to the organic matter that formed the coal. High (Pr/Ph) ratio (1.73-12.47 indicates Mamu samples consisted of terrestrial organic matter with marine incursion deposited under oxic/suboxic-oxic in lacustrine-fluvial/deltaic environment. The distribution patterns of C32-C35 benzohopanes in Mamu samples confirmed the redox condition of organic matter deposition within the Formation. The presence of unsaturated oleanenes in Mamu samples further confirmed their thermal immaturity status. The kerogen types of the samples have capacity to generate both oil and gas. Benzohopanes (C32-C35) and three oleanene isomers; olean-12-ene, olean-13 (18)-ene and olean-18-ene were present in samples collected from Mamu Formation. Coals from Mamu Formation have potential to generate both oil and gas but are presently immature to have formed any significant hydrocarbons.

Keywords

References

REFERENCES

Adam, P., Schaeffer, P. and Albrecht, P. 2006.C40 monoaromatic lycopane derivatives as indicators of contribution of the algal Botryococcus braunii race L to the organic matter of Messel oil shale (Eocene, Germany). Organic Geochemistry 37:584-596.

 

Adedosu, T. A. (2009). Aspects of Organic Geochemistry of Nigerian Coal as a Potential Source-Rock of Petroleum. Ph.d Thesis, University of Ibadan, pp. 93-143.

 

Adeleye, D.R. and Fayose, E.A. (1978), Stratigraphy of the type section of Awe Formation, Odukpani area, southeastern Nigeria. Nig. Jour. Min. Geol., 15, 33-37.

 

Akande, S. O. and Erdtmann, B. D. (1998), Burial metamorphism (thermal maturation) in Cretaceous sediments of the southern Benue trough and Anambra Basin, Nigeria. Amer. Assoc. Petrol. Geol. Bull., 82 (6), 1191-1206.

 

Akande, S. O., Erdtmann, B. D. and Hetenyi, M. (1998), Paleoenvironments, source rock potential and thermal maturity of the Upper Benue rift basins, Nigeria: Implications for hydrocarbon exploration. Org. Geochem., 29, 531-542.

 

Bai, Y., Fang, X., Wang, Y., Kenig, F., Miao, Y. and Wang, Y. 2006.Distribution of aliphatic ketones in Chinese soils: Potential environmental implications. Organic Geochemistry 37:860-869.

 

Balogun, F.A., Mokorbia, C.E., Fasasi, M.K. and Ogundare, F.O. 2003.Natural radioactivity associated with bituminous coal mining in Nigeria.Nuclear Methods And Methods In Physical Resources A 505:444-448.

 

Barthlot, W., Neinhuis, C., Cutler, D., Ditsch, F., Meusel, I., Theisen, I. and Wilhelmi, H. 1998.Classification and terminology of plant epicuticular waxes. Botanical Journal of the Linnean Society 126:237-260.

 

Bechtel, A., Gruber, W., Sachsenhofer, R.F., Gratzer, R. and Püttmann, W. 2001.Organic geochemical and stable carbon isotopic investigations of coals formed in low-lying and raised mires within the Eastern Alps (Austria). Organic geochemistry 32:1289-1310.

 

Bechtel, A., Sachsenhofer, R., F., Markic, M., Gratzer, R., Lucke, A. and Püttmann, W. 2003.Paleoenvironmental implications from biomarker and stable isotope investigations on the Pliocene Velenje lignite seam (Slovenia). Organic Geochemistry 34:1277-1298.

 

Bechtel, A., Markic, M., Sachsenhofer, R.F., Jelen, B., Gratzer, R., Lucke, A., Püttmann, W. 2004. Paleoenvironment of the upper Oligocene Trbovlje coal seam (Slovenia). International Journal of Coal Geology 57: 23–48.

 

Benkhelil, J. (1989), The evolution of the Cretaceous Benue Trough, Nigeria. Jour. Afri. Earth Sci., 8, 251-282.

 

Betrand, P., Behar, F. and Durand, B. 1986.Composition of potential oil from humic coals in relation to their petrographic nature. Organic Geochemistry 10:601-608.

 

Boreham, C.J. and Powell, T.G. 1991. Variation in pyrolysate composition of sediments from the Jurassic Walloon coal measures, eastern Australia as a function of thermal maturation. Organic Geochemistry 17:723-733.

 

Boreham, C.J., Blevin, J.E., Radlinski, A.P. and Trigg, K.R. 2003.Coal as source of oil and gas, a case study from the Bass basin, Australia. APPEA Journal 43.1:117-148.

 

Brassell, S.C. 1992.Biomarkers in recent and ancient sediments: the importance of the diagenetic continuum. In: Whelan, J.K., Farrington, J.W., editors. Organic matter-productivity, accumulation, and preservation in recent and ancient sediments. New York: Columbia University Press. 339-367.

 

Bray, E.E. and Evans, E.D. 1961.Distribution of n-paraffins as a clue to recognition of source beds. Geochimica et Cosmochimica Acta 22:2-15.

 

Caldicott, A.B. and Eglinton, G. 1973.Surface waxes. In: Miller, L.P. (Ed.), Phytochemistry 3,Inorganic Elements and Special Groups of Chemicals, New York: Van Nostrand Reinhold.162. Chemical Geology 20:205-221.

 

Carter, J.D., Barber, W. and Jones, G.P. 1963.The Geology of Parts of Adamawa, Bauchi and Bornu provinces in Northeastern Nigeria.Bulletin of the Geological Survey of Nigeria 30:109.

 

Clark, R.C. and Blummer, M. 1967.Distribution of n-paraffins in marine organisms and sediment. Limnology and Oceanography 12:79-87.

 

Cranwell, P.A. 1974.Monocarboxylic acids in lake sediments:Indicators, derived from terrestrial and aquatic biota of paleoenvironmental trophic levels. Chemical Geology 14:1-4.

 

Curiale, J.A. 1995. Saturated and olefinic terrigenous triterpenoid hydrocarbons in a biodegraded Tertiary oil of northeast Alaska. Organic Geochemistry 23:177-182.

 

Dike, E.F.C. (1976a), Hydrocarbon prospects of Nigerian Basins, Vol. 1: Niger Delta Basin, 142pp. Consultancy Report for The Superior Oil Company, Houston Texas, U.S.A.

 

Dike, E.F.C. (1976b), Hydrocarbon prospects of Nigerian Basins, Vol. 2: Interior Basins- Anambra, Benue, Gongola and Bornu (Chad) Basins, 143-233. Consultancy Report for The Superior Oil Company, Houston Texas, U.S.A.

 

Dike, E.F.C. (1993), Stratigraphy and structure of the Kerri-Kerri Basin, north-eastern Nigeria. Jour. Min. Geol., 29 (2), 77-93.

 

Dike, E.F.C. (2002), Sedimentation and tectonic evolution of the Upper Benue Trough and Bornu Basin, NE Nigeria. Nig. Min. Geosci. Soc. Annual Intern. Conf., Port Harcourt, Nigeria, 2002 (NMGS/ELF Award Winning Paper), Abs. Vol.

 

Dike, E.F.C. and Onumara, I.S. (1999), Facies and facies architecture and depositional environments of the Gombe Formation, Gombe and Environs, NE Nigeria. Sci. Assoc. Nigeria Annual Conf., Bauchi, Nigeria, 1999. Abs. Vol.

 

Duan, Y., Wen, Q.B., Zheng, G., Luo, B.J. and Ma, L. 1997. Isotopic composition and probable origin of individual fatty acids in modern sediments from Ruoergai Marsh and Nansha Sea, China. Organic Geochemistry 27.7/8:583-589.

 

Eglinton, G. and Hamilton, R.J. 1963.The distribution of n-alkanes In: Chemical Plant Taxonomy, ed. London: T.Swain.Academic Press. 187-217.

 

Ekweozor, C.M. and Teln?s, N. 1990.Oleanane parameters: verification by quantitative study of the biomarker occurrence in sediments of the Niger Delta.Organic Geochemistry 16:401-413.

 

Eneogwe, C., Ekundayo, O. and Patterson, B., 2002. Source derived oleanenes identified in Niger Delta oils. Journal of Petroleum Geology 25: 83–95.

 

Enu, I. E. (1987), The palaeoenvironment of deposition of Late Maastrichtian to Paleocene black shale in the eastern     Dahomey Basin, Nigeria.  Geol. Mijinbouw, 66, 15-20

 

Farrimond, P., Taylor, A. and Teln?s, N. 1998.Biomarker maturity parameters. The role of generation and thermal degradation. Organic Geochemistry 29:1181-1197.

 

Ficken, K.J., Li, B., Swain, D.L. and Eglinton, G. 2000.An n-alkane proxy for the sedimentary input of submerged/floating fresh water aquatic macrophytes. Organic Geochemistry 31.7-8:745-749.

 

Fowler, M.G., Abolins, P. and Douglas, A.G. 1986.Monocyclic alkanes in Ordovician organic matter. Organic Geochemistry 10:815-823.

 

Freeth, S.J. (1990), The origin of the Benue Trough.  In: The Benue Trough Structure and Evolution (Edited by Ofoegbu, C.O).  Vieweg and Sohn, Braunchweig, Germany. 217-227.

 

Galimov, E.M. 2006.Isotope Organic Geochemistry.Organic Geochemistry 37:1200-1262.

 

Gonzalez-villa, F.J., Polvillo, O., Boski, T., Moura, D. and de Andres, J.R. 2003.Biomarker patterns in a time-resolved Holocene/terminal Pleistocene sedimentary sequence fro the Guadiana river estuarine area (SW Portugal/Spain border). Organic Geochemistry 34:1601-1613.

 

Grice, K., Schouten, S., Nissembaum, A., Charrach, J. and Sinninghe Damsté, J.S. 1998.A remarkable paradox: Sulfurised freshwater algal (Botryococcus braunii) lipids in an ancient hypersaline euxinic ecosystem. Organic Geochemistry 28:195-216.

 

Haberer, R.M., Mangelsdorf, K., Wilkes, M. and Horsefield, B. 2006.Occurrence and paleoenvironmental significance of aromatic hydrocarbon biomarkers in Oligocene sediments from the Mallik 5L-38 Gas Hydrate Production Research Well (Canada). Organic Geochemistry 37:519-538.

 

Hayes, T.M., Freeman, K.H., Popp, B. and Hoham, C.H. 1990.Compound specific isotope analyses: a novel tool for reconstruction of biogeochemical proceses. Organic Geochemistry 16:1115-1128.

 

Hendrix, M.S., Brassel, S.C., Carrol, A.R. and Graham, S.A. 1995. Sedimentology, organic geochemistry and petroleum potential of Jurassic coal measures: Tarim, Junggar and Turpain basins, Northwest China. American Association of Petroleum Geologists Bulletin 79:929-959.

 

Huang, W.Y. and Meinschein, W. G., 1979. Sterols as ecological indicators. Geochimica et Cosmochimica 43:739–745.

 

Huang, Y., Lockheart, M.J., Collister, J.W. and Eglinton, G. 1995.Molecular and isotopic biogeochemistry of the Miocene clarkia Formation: hydrocarbons and alcohols. Organic Geochemistry 23:785-801.

 

Hunt, J.M. 1991.Generation of gas and oil from coal and other terrestrial organic matter. Organic Geochemistry 17:673-680.

 

Hunt, J.M. 1996.Petroleum Geochemistry and Geology.Second Edition. New York: W.H. Freeman and Company.

 

Hutton, A., Daulay, B., Herudiyanto Nas, C., Pujobroto, A. and Sutarwan, H. 1994.Liptinite in Indonesian Tertiary coals. Energy and Fuels 8:1469-1477.

 

Inaba, T., Suzuki, N., Hirai, A., Sekiguchi, K. and Watanabe, T. 2001. Source rock lithology prediction based on oil diacholestane abundance in the siliceousclastic Akita sedimentary basin, Japan.Organic Geochemistry 32.7: 877-890.

 

Inbus, S.W. and McKirdy, D.M. 1993.Organic geochemistry of Precambrian sedimentary rocks. In: Engel, M.H., Macko, S.A., editors. Organic geochemistry. New York: Pergamon Press. 657-684.

 

Isasken, G.H., Curry, D.J., Yeakel, J.D. and Jensen, A.I. 1998.Controls on the oil and gas potential of humic coals. Organic geochemistry 29:23-44.

 

Jauro, A., Obaje, N.G., Agho, M.O., Abubakar, M.B. and Tukur, A. 2007.Organic geochemistry of Cretaceous Lamza and Chikila coals, upper Benue Trough, Nigeria.Fuel 86:520-532.

 

Johns, R.B. 1986.Biological markers in sedimentary record. Amsterdam: Elsevier Science Publisher.

 

Jones, H. A. (1965), Ferruginous oolites and pisolites.  Jour. Sed. Petrol., 35,838-845.

 

Katz, B. J. 1983. Limitations of Rock-Eval pyrolysis for typing organic matter. Organic Geochemistry 4:195–199.

 

Kagya, M.L.N. 1996. Geochemical characterization of Triassic petroleum source rock in the Mandawa basin, Tanzania. Journal of African Earth Sciences 23.1: 73-88.

 

Killops, S.D. and Killops, V.J. 1993.An introduction to organic geochemistry. UK: Longman Group Ltd. offshore New Zealand sediments. Organic Geochemistry 15:193-197.

 

Killops, S.D. and Killops, V.J. 2005.Introduction to organic geochemistry. Second edition.U.K: Blackwell Publishing Limited.

 

Kogel-Knabner, I. 2002.The macromolecular organic composition of plant and microbial residues as inputs to soil organic matter. Soil Biology & Biochemistry 34:139-162.

 

Köhler, J. and Clausing, A. 2000. Taxonomy and palaeoecology of dinoflagellate cysts from Upper Oligocene freshwater sediments of Lake Enspel, Westerwal area, Germany. Review of Palaeobotany and Palynology 112:39-49.

 

Kotarba, M.J., Clayton, J.L., Rice, D.D. and Wagner, M. 2002.Assesment of hydrocarbon source rock potential of Polish bituminous coals and carbonaceous shales.Chemical Geology 184.1-2:11-35.

 

Kvenvolden, K.A. 1962.Normal paraffin hydrocarbons in sediments from San Francisco Bay, Califonia.American Association of Petroleum Geologists Bulletin 46:1643-1652.

 

Lockheart, M.J., van Bergen, P.F. and Evershed, R.P. 2000.Chemotaxonomic classification of fossil leaves from the Miocene Clarkia lake deposit, Idaho, USA based on n-alkyl lipid distributions and principal component analyses. Organic Geochemistry 31:1223-1246.

 

Mackenzie, A.S., Brassell, S.C., Eglinton, G. and Maxwell, J.R. 1982.Chemical fossils-the geological fate of steroids. Science 217:491-504.

 

Mario, G.G., Ronald, C.S. and Milton, L.L. 1997.Generation and expulsion of petroleum and gas from Almond formation coal, Greater Green river basin, Wyoming. American Association of Petroleum Geologists Bulletin 81:62-81.

 

Matsumoto, G.I. and Watanuki, K. 1990.Geochemical features of hydrocarbons and fatty acids in sediments of the inland hydrothermal environments of Japan.Organic Geochemistry 29:1921-1952.

 

Meinschein, W.G. 1961.Significance of hydrocarbons in sediments and petroleum. Geochimica et. Cosmochimica Acta 22:58-64.

 

Miranda, A.C.M.L, Loureiro, M.R.B. and Cardoso, J.N. 1999.Aliphatic and Aromatic hydrocarbons in Candiota coal samples: novel series of bicyclic compounds. Organic Geochemistry 30:1027-1028.

 

Mitterer, R.M. 1993.The diagenesis of proteins and amino acids in fossil shells. In: Engel, M.H., Macko, S.A., editors:Organic geochemistry, principles and applications. New York: Plenum Press.739-753.

 

Murat, R.C., (1972), Stratigraphy and paleogeography of the Cretaceous and lower Tertiary in southern Nigeria. In: African Geology (Ed. by Dessauvagie, T.F.J. and Whiteman, A.J.), 251-266. Ibadan University press, Ibadan, Nigeria.

 

Nytoft, H.P., Lutnaes, B.F. and Johansen, J.E. 2006.28-Nor-spergulanes, a novel series of rearranged hopanes. Organic Geochemistry 37:772-786.

 

Obaje, N.G. 2000.Biomarker evaluation of the oil-generative potential of organic matter in Cretaceous strata from the Benue Trough, Nigeria.Nigerian Association of Petroleum Explorationists Bulletin 15:1.

 

Obaje, N.G., Ulu, O.K. and Petters, S.W. (1999), Biostratigraphic and geochemical controls of hydrocarbon prospects in the Benue Trough and Anambra Basin, Nigeria. Nig. Assoc. Petrol. Expl. Bull., 14(1), 18-54.

 

Obaje, N. G., Wehner, H., Scheeder, G., Abubakar, M.B and Jauro, A. (2004), Hydrocarbon prospectivity of Nigeria’s inland basins: From the viewpoint of organic geochemistry and organic petrology. Amer. Assoc. Petrol. Geol. Bull., 88(3), 325-353.

 

Obaje, N. G., Attah, D. O., Opeloye, S. A. and Moumouni, A. (2006), Geochemical evaluation of the hydrocarbon prospects of sedimentary basins in Northern Nigeria. Geochem. Jour., 40, 227 – 243.

 

Offodile, M. E. (1976), The geology of the Middle Benue, Nigeria. Spec. Vol. Palaeont. Inst. Uni. Uppsala, 4, 1-166.

 

Ojoh, K. A. (1990), Cretaceous geodynamic evolution of the southern part of the Benue Trough (Nigeria) in the equatorial domain of the South Atlantic: Stratigraphy, basin analysis and paleo-oceanography.  Bull. Cent. Rech. Expl. Prod., Elf-Aquitaine, 14, 419-442.

 

Osazuwa, I. B., Ajakaiye, D. E. and Verheijen, P. J. T. (1981), Analysis of the structure of part of the Upper Benue rift valley on the basis of new geophysical data. Earth  Evol. Sci., 2, 126-135.

 

Otto, A. and Wilde, V. 2003.Sesqui-, di-, and triterpenoids as chemosystematics markers in extant conifers-a review. Botanical Review 67:141-238.

 

Otto, A., Simoneit, B.R.T. and Rember, W.C. 2005.Conifer and angiosperm biomarkers in clay sediments and fossil plants from the Miocene clarkia Formation, Idaho, USA.Organic Geochemistry 36:907-922.

 

Ozcelik, O. and Altunsoy, M. 2005.Organic Geochemical Characteristics of Miocene Bituminous Units in the Beypazari Basin, Central Anatolia, Turkey.The Arabian Journal of Science and Engineering 30.2A: 181-194.

 

Pearsen, M. J. and Obaje, N. G. (2000), Onocerane and other triperpenoids in Late Cretaceous sediments from the Upper Benue Trough of Nigeria: tectonic and palaeoenvironmental.  Amer. Assoc. Petrol. Geol. Bull., 83, 1943-1964.

 

Peters, K.E. and Moldowan, J.M. 1991.Effects of source, thermal maturity, and biodegradation on the distribution and isomerization of homohopanes in petroleum. Organic Geochemistry 17:47-61.

 

Peters, K.E. and Moldowan, J.M. 1993.The Biomarker Guide.Interpreting Molecular Fossils in Petroleum and Ancient Sediments.New Jersey: Prentice-Hall, Englewood Cliffs.

 

Peters, K.E., Walters, C.C. and Moldowan, J.M. 2005.The Biomarker Guide. Biomarkers and Isotopes in the Environment and Human History (I). Cambridge University Press.

 

Petersen, H.I., Ansbjerg, J., Bojesen-Koefoed, J.A. and Nytoft, H.P. 2000.Coalgenerated oil: source rock evaluation and petroleum geochemistry of the Lulita oil field, Danish North Sea.Petroleum Geology 23:55-90.

 

Petters, S. W. (1978), Stratigraphic evolution of the Benue Trough and its implications for the Upper Cretaceous paleography of West Africa. Jour. Geol., 86, 311-322.

 

Petters, S. W. (1979), Maastrichtian arenaceous foraminifera from northwestern Nigeria. Paleontology, 22, 947-963.

 

Petters, S. W. (1980), Biostratigraphy of upper Cretaceous foraminifera of the Benue Trough, Nigeria.  Jour. Fora. Res., 10, 199-204.

 

Petters, S. W. (1982), Central West Africa Cretaceous-Tertiary benthic foraminfera and stratigraphy.   Paleont. (A) 179, 1-104.

 

Petters, S. W. (1991), Regional Geology of Africa. Springer- Verlage, Berlin, 722pp.

 

Petters, S.W. and Ekweozor, C. M. (1982), Petroleum geology of the Benue Trough and southeastern Chad Basin, Nigeria: Amer. Assoc. Petrol. Geol. Bull., 60(8), 1141-1149.

 

Philippi, G.T. 1965. On the depth, time and mechanism of petroleum generation. Geochimica et Cosmochimica Acta 29:1021-1049.

 

Philp, R.P. 1985. Methods in Geochemistry and Geophysics, 23.Fossil Fuel Biomarkers.Applications and spectra. NY: Elsevier Science Publishing Company Inc.

 

Philp, R.P. and Gilbert, T.D. 1986. Biomarker distributions in Australian oils predominantly derived from terrigenous source material. Organic Geochemistry 10: 73-84.

 

Reyment, R.A. (1965), Aspects of the geology of Nigeria. Ibadan. Univ. Press, Ibadan, Nigeria, 145pp.

 

Rullkötter, J., Spiro, B., and Nissenbaum, A. 1985.Biological marker characteristics of oils and asphalts from carbonate source rocks in a rapidly subsiding graben, Dead Sea, Israel.Geochimica et Cosmochimica Acta 49:1357-1370.

 

Rullkötter, J., Peakman, T.M. and ten Haven, H.L. 1994. Early diagenesis of terrigenous triterpenoids and its implications for petroleum geochemistry. Organic Geochemistry 21:215-233.

 

Sabel, M., Bechtel, A., Püttmann, W. and Hoernes, S. 2005.Palaeoenvironment of the Eocene Eckfeld Maar lake (Germany): implications from geochemical analysis of the oil shale sequence. Organic Geochemistry 36:873-891.

 

Sari, A. and Bahtiyar, I. 1999.Geochemical evaluation of the Besikli oil field, Kahta, Adiyaman, Turkey.Marine and Petroleum Geology 16:51-164.

 

Scalan, R.S. and Smith, J.E. 1970.An improved measure of the odd-even predominance in the normal alkanes of sediment extracts and petroleum. Geochimica et. Cosmochimica Acta 34:611-620.

 

Simpson, A. (1954), The Nigeria coalfield. The geology of parts of Onitsha, Owerri and Benue provinces. Bull. Geol. Sur. Nigeria, 24, 1-85.

 

Simoneit, B.R.T., Grimalt, J.O., Wang, T.G., Cox, R.E., Hatcher, P.G. and Nissenbaum, A. 1986.Cyclic terpenoids of contemporary resinous plant detritus and of fossil woods, amber and coal. Organic Geochemistry 10:877-889.

 

Simoneit, B.R.T. 1998.Biomarker PAHs in the environment. In: Neilson, A., Hutzinger, O., editors. The handbook of environmental chemistry. Berlin: Springer Verlag. 175-221.

 

Simoneit, B.R.T. 2002.Molecular Indicators of Past Life.The Anatomical Record 268:186-195.

 

Sinninghe Damsté, J.S., Kenig, F., Koopmans, M.P., Koster, I., Schouten, S., Hayes, J.M. and De Leeum, J.W. 1995.Evidence for gammacerane as an indicator of water coloumn stratification. Geochim et Cosmochim Acta 59:1895-1900.

 

Stefanova, M., Oros, D.R., Otto, A. and Simoneit, B.R.T. 2002.Polar aromatic biomarkers in the Miocene Maritza-East lignite, Bulgaria.Organic Geochemistry 33:1079-1091.

 

Stefanova, M., Markova, K., Marinov, S. and Simoneit, B.R.T. 2005. Molecular indicators for coal-forming vegetation of the Miocene Chukurovo lignite, Bulgaria. Fuel 84:1830–1838.

 

Ten Haven, H.L. and Rulkotter, J. 1988.The diagenetic fate of taraxer-14-ene and oleanene isomers. Geochimica et Cosmochimica Acta 52:2543-2548.

 

Tissot, B., Pelet, R. and Roucache, J. 1977.Alkanes as geochemical fossils indicators of geological environments. In: Campus, R., Goni, J. (Eds.), Advances in Organic Geochemistry 1975,Enadimsa, Madrid. 117-154.

 

Tissot, B.T. and Welte, D.H. 1984. Petroleum Formation and Occurrences.Second Edition. Berlin: Springer-Verlag.

 

Treibs, A. 1934.The occurrence of Chlorophyll derivatives in an oil shale of the upper Triassic.Annalen 517:103-114.

 

Tuo, J. and Li, Q. 2005.Occurrence and distribution of long-chain acyclic ketones in immature coals. Applied Geochemistry 20:553-568.

 

Tuo, J. Ma, W., Zhang, M. and Wang, X. 2007.Organic geochemistry of the Dongsheng sedimentary uranium ore deposits, China.Applied Geochemstry 22:1949-1969.

 

Tyson, R.V.1995. Sedimentary Organic Matter.In:Organic Facies and Palynofacies.New York: Chapman and Hall.309-315.

 

Volkman, J.K. and Maxwell, J.R. 1986.Acyclic isoprenoids as biological markers. In: Johns, R.B. (Ed.), Biological Markers in Sedimentary Record. Amsterdam: Elsevier .1-42.

 

Volkman, J.K. 1988. The biological marker compounds as indicators of the depositional environments of petroleum source rocks. In: Fleet, A.J., Kelts, K., Talbot, M.R. (Eds.), Lacustrine Petroleum Source Rocks. Geological Society Special Publication 40:103-122.

 

Volkman, J.K., Barrett, S.M., Blackburn, S.I., Mansour, M.P., Sikes, E.L. and Gelin, F. 1998. Microalgal biomarkers: a review of recent research developments. Organic Geochemistry 29:1163-1179.

 

Volkman, J.K. 2005.Sterols and other triterpenoids: source specificity and evolution of biosynthetic pathways. Organic geochemistry 36:139-159.

 

Whiteman, A. J. (1982), Nigeria: its Petroleum Geology, Resources and Potential. 1, 176pp; 2, 238pp. Graham and Trotman, London, UK.

 

 

Wilkes, H., Ramrath, A. and Negendank, J. F. W. 1999. Organic geochemical evidence for environmental changes since 34,000 yrs BP from Lago di Mezzano, central Italy. Journal of Paleolimnology 22:349–365.

 

Wright, J. B. (1981), Review of the origin and evolution of the Benue Trough in Nigeria. Earth Evol. Sci., 2, 98-103.

 

Yangming, Z., Huanxin, W., Aiguo, S., Digang, L. and Dehua, P. 2005.Geochemical characteristics of Tertiary saline lacustrine oils in the Western Qaidam Basin, northwest China.Applied Geochemistry 33:1225-1240.

 

Yessalina, S., Suzuki, N., Nishita, H. and Waseda, A. 2006.Higher plant biomarkers in Paleogene crude oils from the Yufutsu oil- and gas field and offshore wildcats, Japan Journal of Petroleum Geology 29.4:327-336.

 

Zaborski, P. M. (1998), A review of the Cretaceous system in Nigeria. Afri. Geol. Rev., 5(4), 385-483.