Evaluation of Aquifer Protective Capacity and Soil Corrosivity Using Geoelectrical Method

Authors: M. T. Tsepav, Y. Adamu, M. A. Umar

Abstract:

A geoelectric survey was carried out in some parts of Angwan Gwari, an outskirt of Lapai Local Government Area on Niger State which belongs to the Nigerian Basement Complex, with the aim of evaluating the soil corrosivity, aquifer transmissivity and protective capacity of the area from which aquifer characterisation was made. The G41 Resistivity Meter was employed to obtain fifteen Schlumberger Vertical Electrical Sounding data along profiles in a square grid network. The data were processed using interpex 1-D sounding inversion software, which gives vertical electrical sounding curves with layered model comprising of the apparent resistivities, overburden thicknesses, and depth. This information was used to evaluate longitudinal conductance and transmissivities of the layers. The results show generally low resistivities across the survey area and an average longitudinal conductance variation from 0.0237Siemens in VES 6 to 0.1261Siemens in VES 15 with almost the entire area giving values less than 1.0 Siemens. The average transmissivity values range from 96.45 Ω.m2 in VES 4 to 299070 Ω.m2 in VES 1. All but VES 4 and VES14 had an average overburden greater than 400 Ω.m2, these results suggest that the aquifers are highly permeable to fluid movement within, leading to the possibility of enhanced migration and circulation of contaminants in the groundwater system and that the area is generally corrosive.

Keywords: Geoelectric survey, corrosivity, protective capacity, transmissivity.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1110083

References:

[1] Keller G., V. and Frischknecht, F. C. (1966). Electrical Methods in Geophysical Prospecting. Pergamon Press, Oxford, New York, Toronto, Sydney, Braunsckweig.
[2] Krumbein, W.C., and Sloss, L. L. (1963). Stratigraphy and Sedimentation. W. H. Freeman and Co., San Francisco, 660 pp.
[3] Brousse, J. J. (1963). Modern geophysical methods for subsurface water exploration: Geophysics, v. 28/4, p. 634-635.
[4] Ako, B.D., and Osondu, V.C. (1986). Electrical resistivity of the Kerri- Kerri Formation, Darazo, Nigeria: Journal of African Earth Sciences, v. 5/5, p. 527-534.
[5] Olorunniwo, M.A., and Olorunfemi, M.O. (1987). Geophysical Investigation for Groundwater in Precambrian Terrain, A case history from Ikare, Southwest Nigeria. Journal of African Earth Sciences, v. 6, p. 787-796.
[6] Olorunfemi, M.O., and Fasuyi, S.A. (1993). Aquifer Types and the Geoelectric Hydrogeologic Characteristics of Parts of the Central Basement Terrain of Nigeria, Niger State. Journal of African Earth Sciences, v. 16/3, p 309-317.
[7] Ayolabi, E.A., Adeoti, L., Oshinlaja, N.A., Adeosuni, I.O., and Idowu, O.I. (2009). Seismic Refraction and Resistivity Studies of part of Igbogbo Township, Southwest Nigeria: Journal of Science Research Development, v. 11, p. 42–61. Balkan Geophysical Society 1, 3-6.
[8] Osuagwu, B.C. (2009). Geophysical investigation for groundwater in a difficult terrain around Modomo Area, Ife, Osun State: Unpublished Bachelor of Science Thesis, Obafemi Awolowo University, Ile-Ife, Osun State, p. 88.
[9] Sustainable Human Settlement Consult Limited, (2004): Ibrahim Badamasi Babangida University Master Plan.
[10] Obaje, N.G, Lar, A., Nzegbuna, A., Moumouni, A., Chaanda, M., and Goki, N. (2006). Geology and Mineral Resources of Nasarawa State; An investor’s Guide. Nasarawa Scientifique, 2, No. 1
[11] Oyawoye, M.O. (1964). The Geology of the Nigerian Basement Complex. Journal of the Nigerian Mining, Geological and Metallurgical Society, v. 1, p. 87-482.
[12] Rahaman, M.A. (1973). The Geology of the District around Iseyin, Western Nigeria: Unpublished Ph.D Thesis, University of Ibadan, p. 268.
[13] Rahaman, M.A. (1976). Review of the Basement Geology of Southwest Nigeria, Geology of Nigeria, in, C.A. Kogbe (ed.), Geology of Nigeria: Elizabethan Publishing, p. 41-58.
[14] Rahaman, M.A. (1988). Recent Advances in the Study of the Basement Complex of Nigeria: Precambrian Geology of Nigeria, G.S.N, p. 11-41.
[15] Odeyemi, I.B., (1978). Orogenic Events in the Precambrian Basement of Nigeria, West Africa: Geol. Rdsch, v, 70, 879-909.
[16] Mohamed, A.S. (1975). Vertical Electrical Resistivity Soundings to Locate Ground Water Resources: A Feasibility Study. Virginia Water Resources Research Center Bulletin; 73: 7. New York.
[17] Olorunfemi, M. O., Ojo, J. S. and Akintunde, O.M. (1999). “Hydrogeophysical evaluation of the groundwater potential of the Akure metropolis, Southwestern Nigeria”. Journal of Mining and Geology Vol. 35(2) 1999, pp. 207 – 228.
[18] Henriet, J. P. (1975). Direct applications of the Dar Zarrouk parameters in ground water surveys. Geophysical Prospecting, 24 (3): 44–353.
[19] Nwankwo, C. N. and Ehirim, C.N. (2010). Evaluation of aquifer characteristics and groundwater quality using geoelectrical method in Choba, Port Harcourt. Archives of applied science research, 2(2):396- 403.