Lithological Description of Bornu Basin, Northeastern Nigeria Using Gamma Ray Log and Relative Acoustic Impedance Attribute

Umeghalu C.O.¹ , Egwuonwu G.N.² , Ezeobi C.F.³

Section:Research Paper, Product Type: Journal-Paper
Vol.11 , Issue.4 , pp.26-32, Aug-2023

Online published on Aug 31, 2023

Copyright © Umeghalu C.O., Egwuonwu G.N., Ezeobi C.F. . This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
 

View this paper at   Google Scholar | DPI Digital Library

XML View     PDF Download

How to Cite this Paper

Abstract :
The Bornu Basin, which spans across Chad Republic, Cameroon, and Niger Republic, is an extensional basin that originated from the mechanical separation of the African crustal plate during the Cretaceous period. The geographical boundaries of the study area are defined by latitude 11.750 N to 13.000 N and longitude 12.000 E to 14.000 E. To better understand the distribution of rocks within the basin suitable for hydrocarbon accumulation, a lithological analysis was conducted using gamma ray logs and relative acoustic impedance attributes. By examining changes in gamma ray signatures across multiple wells, the formation tops of Chad, Kierri-kierri, Fika, and Gongila were identified, marked, and correlated across the wells. The well sections were aligned with the Chad formation, encountered at depths ranging from 0 to 220 meters across the wells. Further analysis of lithostratigraphy and seismic attributes, utilizing specialized seismic interpretation software, allowed for the interpretation of the basin`s characteristics and the identification of potential prospects. The gamma ray log analysis revealed that the study area is characterized by interbedded layers of sand and shale. Additionally, lithologic correlation confirmed the presence of both basin and intra-reservoir seals. The relative acoustic impedance survey provided stratigraphic information, further supporting the presence of reservoir and seal rocks within the study area.

Key-Words / Index Term :
Gamma Ray, Lithology, Stratigraphy, Acoustic Impedance, Shale, Well Correlation, Synthetic Seismogram, Density.

References :
[1] A. A. Avbovbo, E. O. Ayoola and S. A. Osahon, “Depositional and structural styles in Chad Basin of Northeastern Nigeria”, AAPG, Vol.70, Issue.121, pp.1787–1798, 1986.
[2] C. F. Ezeobi, G. N. Egwuonwu and I.U. Chibuogwu. “Reservoir Identification in Bornu Basin, Northeastern Nigeria Based on Well Log Analysis”, International Journal of Scientific Research in Physics and Applied Sciences, Vol.11, Issue.1, pp.7-16. 2023a
[3] N. G. Obaje, H. Wehner and G. Scheeder, “Hydrocarbon prospectivity of Nigeria’s inland basins: From the viewpoint of organic geochemistry and organic petrology”, AAPG Bulletin, 2004, Vol.87, pp.325–353, 2004.
[4] I. Hamza and I. Hamidu, “Hydrocarbon resource potential of the Bornu basin northeastern Nigeria”, Global Journal of Geological Sciences, Vol.10, Issue.1, 2012.
[5] S. P. Braide, “Petroleum geology of the southern Bida Basin Nigeria”, American Association of Petroleum Geologists, Vol.74, Issue.5, pp.717 - 725, 1990.
[6] G. J. Genik “Regional framework structure and petroleum aspects of the rift basins in Niger, Chad and Central African Republic (C.A.R.)”, Tectonophysics, Vol. 213, pp.169–185, 1992.
[7] C. O. Ajayi and D. E. Ajakaiye, “The Origin and Peculiarities of the Nigeria Benue Trough. Another look from recent gravity data obtained from middle Benue”, Tectonophysics, Vol.12, pp.286-329, 1981.
[8] NGSA, “Geological and Mineral Resources Map Album”, Nigerian Geological Survey Agency, 2006.
[9] C. F. Ezeobi, G. N. Egwuonwu and I.U. Chibuogwu, “Reservoir Identification in Bornu Basin, Northeastern Nigeria Using Seismic Attributes Analysis”. International Journal of Scientific Research in Multidisciplinary Studies, Vol.9, Issue.2, pp 1-8, 2023b.
[10] S. W. Petter and C. M. Ekweozor, “petroleum Geology of Benue Trough and southeastern Chad Basin Nigeria”, GEOLOGIC NOTES, AAPG Bulletin 66, 1141-1149, 1982.
[11] K. O. Omosanya, A. A. Akinmosin and N. A. Adio, “Hydrocarbon potential of the Nigerian chad basin from wireline logs”, Indian Journal of Science, Vol. 4, Issue.12, pp.1668-1675, 2011.
[12] C. N. Nwankwo and A. S. Ekine, “ Geothermal gradients in the Chad basin, Nigeria from bottom hole temperature logs, Int Journal of Physical Sciences, Vol.4, Issue.12, pp.777-783, 2009.
[13] J. A. Adeyinka, S. P. Ola and S. O. Olabode, “Possible Bornu Basin Hydrocarbon Habitat”, International Journal of Geoscience, Vol.5, Issue.9, 2014.
[14] S. A. Aminu and M. Whiteworth, “Integrated well log and 2-D seismic data interpretation to image subsurface stratigraphy and structure in Northeastern Bornu Basin”, Journal of African Earth Science, Vol.121, pp.1 – 15, 2016
[15] S. K. Ahmed, K. Liu, H. Moussa, J. Liu, A. H. Ahmed and L. K. Kra, “Assessment of petroleum system elements and migration pattern of Borno (Chad) Basin, Northeastern Nigeria”, Journal of petroleum science and engineering, Vol.208, 2022.
[16] C. N. Didi, I. I. Obiadi, S. E. Okeke, S. N. Anakor and M. K. Ikomi, “Lithostratigraphic interpretation and analysis of the depositional environment of Nigerian Chad basin using well log and seismic data”, Meridian Journal of Physical Science, Vol.2, Issue.1, 2022.
[17] S. Chopra and J. M. Kurt, “Seismic attributes—A historical perspective”, Geophysics, Vol. 70, Issue.5, pp.3SO?28SO, 2005.
[18] M. T. Taner, “Seismic attributes”, CSEG Recorder, September, pp.48–56, 2001
[19] K. D. Opeyemi and A. P. Aizebeokhai “Seismic attribute analysis for reservoir characterization, offshore Niger delta”, Petroleum and Coal, Vol.57, Issue.6, pp.619 – 628, 2016.
[20] F. W. Schroeder, “IRIS Geoscience Education and Public Outreach program”, https://www.iris.edu, 2018.