Grain size studies of the Campanian-Maastrichtian Lokoja Formation have
been investigated. The sand particles exhibit low sphericity which are
angular to sub-angular. Histograms showed unimodal and bimodal trends
and is predominantly asymmetrical with varying modal class, which may be
due to variation in transporting medium energy. The graphic mean ranges
from 0.1ф (coarse grained) to 1.35ф (medium grained) while the is
average 0.81ф (coarse grained). The dominance of coarse grained
particles and dearth of fine sands implies strong to moderate energy
conditions during deposition. The standard deviation ranges from
0.08ф-0.60ф (very well sorted to moderately well sorted); average of
0.40ф (well sorted), which may be due to rapid back and forth movement
of the depositing medium. The skewness ranges between -0.39 and 0.59
(strongly coarse skewed to strongly fine skewed), while the graphic
kurtosis ranges between 0.77 and 2.5 indicating playtykurtic to very
leptokurtic and this variation may be due to some of the deposits being
sorted in high-energy environment elsewhere. A Bivariate plot (simple
skewness vs. standard deviation) shows the samples plotting mainly in
the river sand zone. Another plot of mean size vs. standard deviation
also shows the samples appearing in the river sand zone; other
granulometric parameters that discriminates between river channel
deposits, overbank deposits and overbank-pool deposits shows that the
Lokoja sandstones plotted in the river channel zone. Linear discriminant
analyses signpost a shallow marine beach environment. From the Passega
diagram, majority of the samples plotted outside the featured fields,
only three samples plotted within the diagnostic parameter zone around
the uniform suspension-SR zone.
The study contributes to the existing literature on the sandstone facies
of the Lokoja Formation in the Mid Niger Basin based on granulometric
parameters to establish the depositional environment of the sandstone
and sedimentary process that occurred during deposition.
F. P. Shepard and D. G. Moore, "Central texas coast sedimentation: Characteristics of sedimentary environment, recent history and diagenesis: Part 2," American Association of Petroleum Geologists Bulletin, vol. 39, pp. 1463-1593, 1955.View at Google Scholar | View at Publisher
R. L. Folk and W. C. Ward, "Brazos river bar: A studv in the significance of gram size parameters," Journal of Sedimentary Petrology, vol. 27, pp. 3-26, 1957. View at Google Scholar | View at Publisher
C. C. Mason and R. L. Folk, "Differentiation of beach, dune and aeolian flat environments by grain size analysis, Mustang Island, Texas," Journal of Sedimentary Petrology, vol. 28, pp. 211-226, 1958. View at Google Scholar | View at Publisher
F. P. Shepard, "Gulf coast barriers. In: Recent sediments, Northwest Gulf of Mexico," American Association of Petroleum Geologists Bulletin, pp. 197-220, 1960.
J. E. Callahan, "Heavy minerals in stream sediments from Churchill falls, labrador - an aid to bedrock mapping," Canadian Journal of Earth Sciences, vol. 17, pp. 244-253, 1980. View at Google Scholar | View at Publisher
G. M. Friedman, "Distinction between Dune, Beach and river sands from their textural characteristics," Journal of Sedimentary Petrology, vol. 31, pp. 514-529, 1961. View at Google Scholar | View at Publisher
G. M. Friedman, "Dynamic processes and statistical parameters compared for grain frequency distribution or beach and river sands," Journal of Sedimentary Petrology, vol. 37, pp. 327-354, 1967. View at Google Scholar | View at Publisher
O. M. Friedman, "Address of the retiring President of the International Association of Sedimentologists: Differences in size distributions of populations of particles among sands of various origins," Sedimentology, vol. 26, pp. 3-32, 1979. View at Google Scholar | View at Publisher
J. E. Klovan, "The use of factor analysis in determining depositional environments from grain-size distributions," Journal of Sedimentary Petrology, vol. 36, pp. 115-125, 1966. View at Google Scholar | View at Publisher
N. M. Shukri, "The mineralogy of some Nile sediments," Quarterly Journal of the Geological Society, vol. 105, pp. 511-534, 1949. View at Publisher
T. H. Van Andel, Provenance, transport and deposition of Rhine sediments: A heavy mineral study on river sands from the drainage area of the Rhine. The Netherlands: Veenman en Zonen, Wageningen, 1950.
A. C. Morton and D. Smale, "The effects of transport and weathering on heavy minerals from the Cascade River, New Zealand," Sedimentary Geology, vol. 68, pp. 117-123, 1990. View at Google Scholar | View at Publisher
A. C. Morton and M. J. Johnsson, Factors influencing the composition of detrital heavy mineral suites in Holocene sands of the Apure River drainage basin, Venezuela. In: M.J. Johnsson and A. Basu (Editors), Processes controlling the composition of clastic sediments. Boulder, Colorado: Geological Society of America Special Paper, 1993.
P. Allen and M. Mange-Rajetzky, "Sediment dispersal and palaeohydraulics of Oligocene rivers in the Eastern Ebro Basin," Sedimentology, vol. 29, pp. 705-716, 1982. View at Google Scholar | View at Publisher
J. Preston, "The provenance of Triassic continental sandstones from the Beryl Field, Northern North Sea: Mineraological, geochemical, and sedimentological constraints," Journal of Sedimentary Research, vol. 72, pp. 18-29, 2002.
R. M. Flores and G. L. Shidler, "Factors controlling heavy mineral variations on the South texas outer continental shelf," Journal of Sedimentary Petrology, vol. 48, pp. 269-280, 1978. View at Google Scholar | View at Publisher
T. Weissbrod and J. Nachmias, "Stratigraphic significance of heavy minerals in the Late Precambrian- Mesozoic clastic sequence (Nubian Sandstone) in the Near East," Sedimentary Geology, vol. 47, pp. 263-291, 1986. View at Google Scholar | View at Publisher
A. C. Morton, B. Humphreys, D. A. Dharmayanti, and Sundoro, "Palaeogeographic implications of the heavy mineral distribution in Miocene sandstones of the North Sumatra Basin," Journal of Southeast Asian Earth Sciences, vol. 10, pp. 177-190, 1994. View at Publisher
A. C. Morton, Provenance of brent group sandstones: Heavy mineral constraints. In: A.C. Morton, R.S. Haszeldine, R.S. Giles and S. Brown (Editors), Geology of the brent group. London: Geological Society of London, 1992.
J. C. Lihou and M. A. Mange-Rajetzky, "Provenance of the Sardona Flysch, Eastern Swiss Alps: Example of high-resolution heavy mineral analysis applied to an ultrastable assemblage," Sedimentary Geology, vol. 105, pp. 141-157, 1996. View at Google Scholar | View at Publisher
D. R. Adeleye, "Stratigraphy and Sedimentation of the upper cretaceous strata around Bida, Nigeria," University of Ibadan, Unpublished Ph.D Thesis, 1971.
D. R. Adeleye and T. F. J. Dessauvagie, Stratigraphy of the Niger embayment, near Bida, Nigeria. In: Dessauvagie, T.F.J., Whiteman, A.J. (Eds.), African geology: University of Ibadan Press, 1972.
R. E. Jan Du Chene, O. S. Adegoke, S. A. Adediran, and S. W. Petters, "Palynology and foraminifera of the Lokoja Sandstone (Maastrichtian), Bida Basin, Nigeria," Revista Espanola de Micropaleontotologia, vol. 10, pp. 379 – 393, 1978. View at Google Scholar
S. O. Akande, O. J. Ojo, and K. Ladipo, Upper cretaceous sequences in the Southern Bida Basin, Nigeria. A field guidebook. Ibadan: Mosuro Publishers, 2005.
O. J. Ojo and S. O. Akande, "Sedimentological and palynological studies of the patti formation. Southeastern Bida Basin, Nigeria: Implications for paleoenvironments and paleogeography," Nigeria Association of Petroleum Explorationists Bulletin, vol. 19, pp. 61-77, 2006. View at Google Scholar
O. J. Ojo and S. O. Akande, "Microfloral assemblage, age and paleoenvironment of the upper cretaceous Patti formation, South Eastern Bida Basin, Nigeria," Journal of Mining and Geology, vol. 44, pp. 71-82, 2008. View at Google Scholar | View at Publisher
S. B. Ojo and D. E. Ajakaiye, Preliminary interpretation of gravity measurements in the Middle Niger Basin area, Nigeria, In: (CA Kogbe, Ed.). Lagos: Geology of Nigeria, Elizabethan Publishing Co, 1976.
C. A. Kogbe, D. E. Ajakaiye, and G. Matheis, "Confirmation of rift structure along the middle- Niger Valley, Nigeria," Journal of African Earth Sciences, vol. 1, pp. 127-131, 1981.
S. B. Ojo and D. E. Ajakaiye, Preliminary interpretation of gravity measurements in the middle Nıger Basin are, Nigeria. In: Kogbe, C.A. (Ed.), Geology of Nigeria, 2nd ed. Lagos: Elizabethan Publishing Company, 1989.
J. O. Idowu and E. I. Enu, "Petroleum geochemistry of some late cretaceous shale from the Lokoja Sandstone of Middle Niger Basin, Nigeria," Journal of African Earth Sciences, vol. 14, pp. 443–455, 1992.View at Google Scholar | View at Publisher
N. G. Obaje, M. K. Musa, A. N. Odoma, and H. Hamza, "The Bida Basin in North-Central Nigeria: Sedimentology and petroleum geology," Journal of Petroleum and Gas Exploration Research, vol. 1, pp. 001-013, 2011. View at Google Scholar
J. Osokpor and J. Okiti, "Sedimentological and paleodepositional studies of outcropping sediments in parts of Southern Middle Niger Basin," International Journal of Science and Technology, vol. 2, pp. 840-846, 2013. View at Google Scholar
H. A. Jones, "The oolitic ironstone of Agbaja Plateau, Kabba Province," Record of the Geological Survey of Nigeria, pp. 20 – 43, 1958.
S. B. Ojo, "Middle Niger Basin revisited: Magnetic constraints on gravity interpretations," presented at the Abstract, 20th Conference of the Nigeria Mining and Geosciences Society, Nsukka, 1984.
S. P. Braide, "Syntectonic fluvial sedimentation in the central Bida Basin," Journal of Mining and Geology, vol. 28, pp. 55-64, 1992. View at Google Scholar
W. Q. Kennedy, "The inﬂuence of basement structure on the evolution of the coastal (Mesozoic and Tertiary) basins. In: Recent Basins around Africa," in Proceedings of the Institute of Petroleum Geologists Society, London, 1965, pp. 35–47.
A. Whiteman, Nigeria: Its petroleum geology, resources and potential vol. 1 and 2. London: Graham and Trotman, 1982.
S. P. Braide, "Geological development, origin and energy mineral resource potential of the Lokoja formation in the Southern Bida Basin," Journal of Mining and Geology, vol. 28, pp. 33-44, 1992. View at Google Scholar
W. Russ, "The Minna-Birnin Gwari belt," Report of Geological Survey of Nigeria, 1930.
T. F. G. Dessauvagie, "Explanatory note to the geological map of Nigeria, scale 1: 1,000,000," Journal of Mining Geology Nigerian Meteorological Society, vol. 9, p. 28, 1975.
G. Nichols, Sedimentology and stratigraphy, 2nd ed. UK: Wiley-Blackwell Publishers, 2009.
>G. M. Friedman, "Distinction between dune, beach, and river sands from their textural characteristics," Journal of Sedimentary Petrology, vol. 31, pp. 514-529, 1961. View at Google Scholar | View at Publisher
S. J. Boggs, Petrology of sedimentary rocks, 2nd ed. UK: Cambridge University Press, 2009.
J. Baruah, P. Kotoky, and J. Sarma, "Textural and geochemical study on river sediments: A case study on the Jhanji River, Assam," Journal of the Indian Association of Sedimentologists, vol. 16, pp. 195–206, 1997.
A. K. Ray, S. C. Tripathy, S. Patra, and V. V. Sarma, "Assessment of Godavari Estuarine mangrove ecosystem through trace metal studies," Environment International, vol. 32, pp. 219–223, 2006. View at Google Scholar | View at Publisher
G. M. Friedman, "On sorting, sorting coeflicients, and the lognormality of the grain-size distribution of sandstones," Journal of Geology, vol. 70, pp. 737-753, 1962. View at Google Scholar | View at Publisher
E. Mycielska-Dowgiałło, Metody badań cech teksturalnych osadów klastycznych i wartość interpretacyjna wyników [Research methods for textural features of clastic deposits and the significance of interpretational results]. [In:] E. Mycielska-Dowgiałło & J. Rutkowski (Eds): Badania cech teksturalnych osadów czwartorzędowych i wybrane metody oznaczania ich wieku [Research into the textural features of quaternary sediments and some dating methods]. Warsaw: The Family Alliance School of Higher Education Press, 2007.
E. Mycielska-Dowgiałło and M. Ludwikowska-Kędzia, "Alternative interpretations of grain-size data from quaternary deposits," Geologos, vol. 17, pp. 189–203, 2011. View at Google Scholar | View at Publisher
M. Ludwikowska-Kędzia, Ewolucja środkowego odcinka doliny rzeki Belnianki w późnym glacjale i holocenie [Evolution of the middle segment of the Belnianka River valley in the Late Glacial and Holocene]. Warsaw: Dialog Press, 2000.
S. J. Blott and P. Kenneth, "Gradistat: A grain size distribution and statistics package for the analysis of unconsolidated sediments," Earth Surface Processes and Landforms, vol. 26, pp. 1237-1248, 2001. View at Google Scholar | View at Publisher
This study received no specific financial support.
The author declares that there are no conflicts of interests regarding the publication of this paper.
The author acknowledges the assistance of the 2012 session final year students who participated in the fieldwork.