Back
 JWARP  Vol.8 No.3 , March 2016
Geoelectric Evaluation of Groundwater Potential and Vulnerability of Overburden Aquifers at Onibu-Eja Active Open Dumpsite, Osogbo, Southwestern Nigeria
Abstract: Electrical resistivity method was used to assess groundwater potential and vulnerability of overburden aquifers at Onibu-Eja active open dumpsite, Osogbo, Southwestern Nigeria. Eighteen Vertical Electrical Sounding (VES) points and five 2-D imaging profiles established in five traverses at the periphery of the dumpsite were surveyed and analysed. The subsurface comprised of thin topsoil (resistivity 65 - 998 Ωm); heterogeneous weathered layer with resistivity 63 - 333 Ωm and thickness 0.7 - 8.5 m; weathered basement (resistivity 31 - 1253 Ωm and thickness 0.7 - 27.0 m) and fractured/fresh basement (resistivity 36 - 6213 Ωm). The 2-D inverse model of the profiles delineated low resistivity values ranging from 5 to 100 Ωm at a depth range of 10 - 20 m along traverses TR1-TR3 which is attributed to leachate percolation close to the dumpsite. The weathered basement was inclined relative to the dumpsite. The total overburden thickness varies from 6.9 to 33.7 m, with 20 and 40 m generally recommended as productive for groundwater abstraction in Southwestern Nigeria occurring in 61% of the area. Further, about 85% of the weathered layer resistivity values fall within medium groundwater potential (100 - 250 Ωm) and high groundwater potential (>250 Ωm). The ranking of groundwater potential as a function of saprolite (weathered basement) resistivity showed that 72% of the study area is characterized by optimum weathering (20 - 100 Ωm) and is classified as good groundwater potential. Fractured basement covered <30% of the study area. The evaluation of aquifer protective capacity has helped to classify the area into moderate, weak and poor protective capacities with moderate protective capacity zone covering 72%.
Cite this paper: Ugwu, N. , Ranganai, R. , Simon, R. and Ogubazghi, G. (2016) Geoelectric Evaluation of Groundwater Potential and Vulnerability of Overburden Aquifers at Onibu-Eja Active Open Dumpsite, Osogbo, Southwestern Nigeria. Journal of Water Resource and Protection, 8, 311-329. doi: 10.4236/jwarp.2016.83026.
References

[1]   Margat, J. and van der Gun, J. (2013) Groundwater around the World: A Geographic Synopsis. CRC Press/Balkema. Leiden.

[2]   Rahaman, M.A. (1988) Recent Advances in the Study of the Basement Complex of Nigeria. In Precambrian Geology of Nigeria, Geological Survey of Nigeria, Kaduna South, 11-43.

[3]   Al-Garni, M.A. (2009) Geophysical Investigations for Groundwater in a Complex Subsurface. Terrain, Wadi Fatima, KSA: A Case History. Jordan Journal of Civil Engineering, 3, 118-136.

[4]   Barker, R.D. (2001) Imaging Fractures in Hard Rock Terrain. University of Birmingham, UK.
http://www.bham.ac.uk/EarthSciences/research/hydro/envgeo/

[5]   Efe, S.I. (2002) Urban Warming in Nigerian Cities. The Case of Warri Metropolis. African Journal of Environmental Studies, 3, 160-168.

[6]   Koefoed, O.C. (1979) Geosounding Principles 1: Resistivity Sounding Measurements. Elsevier Science Publishing Company, Amsterdam.

[7]   McDowell, P.W. (1979) Geophysical Mapping of Water Filled Fracture Zones in Rocks. International Association of Engineering Geology Bulletin, 19, 258-264.
http://dx.doi.org/10.1007/BF02600485

[8]   Ayolabi, E.A., Adedeji, J.K. and Oladapo, I.M. (2003) A Geoelectric Mapping of Ijapo, Akure South Western Nigeria and Its Hydrogeological Implications. Global Journal of Pure and Applied Sciences, 10, 441-446.

[9]   Ayolabi, E.A., Folorunso, A.F., Eleyinmi, A.F., Esther, O. and Anuyah, E.O. (2009) Applications of 1D and 2D Electrical Resistivity Methods to Map Aquifers in a Complex Geologic Terrain of Foursquare Camp, Ajebo, Southwestern Nigeria. The Pacific Journal of Science and Technology, 10, 657-666.

[10]   Sharma, S.P. and Baranwal, V.C. (2005) Delineation of Groundwater-Bearing Fracture Zone in a Hardrock Area Integrating Very Low Frequency Electromagnetic and Resistivity Data. Journal of Applied Geophysics, 57, 155-166.
http://dx.doi.org/10.1016/j.jappgeo.2004.10.003

[11]   Griffiths D.H. and Barker, R.D. (1993) Two-Dimensional Resistivity Imaging and Modeling in Areas of Complex Geology. Journal of Applied Geophysics, 29, 21-26.
http://dx.doi.org/10.1016/0926-9851(93)90005-J

[12]   Loke, M.H. (2000) A Practical Guide to 2-D and 3-D Surveys. http://www.heritagegeophysics.com

[13]   Zhou, Q.Y., Matsui, H. and Shimada, J. (2004) Characterization of the Unsaturated Zone around a Cavity in Fractured Rocks Using Electrical Resistivity Tomography. Journal of Hydraulic Research, 42, 25-31.
http://dx.doi.org/10.1080/00221680409500044

[14]   Roa, B.V., Prasad, Y.S. and Reddy, K.S. (2013) Hydrogeophysical Investigations in a Typical Khondalitic Terrain to Delineate the Kaolinised Layer Using Resistivity Imaging. Journal Geological Society of India, 81, 521-530.
http://dx.doi.org/10.1007/s12594-013-0067-x

[15]   Rahaman, M.A. (1989) Review of the Basement Geology of Southwestern Nigeria. In: Kogbe, C.A., Ed., Geology of Nigeria, Elizabeth Publishing Co., Nigeria, 41-58.

[16]   Oyelami, A.C., Ojo, A.O., Aladejana, J.A. and Agbede, O.O. (2013) Assessing the Effect of a Dumpsite on Groundwater Quality: A Case Study of Aduramigba Estate within Osogbo Metropolis. Journal of Environment and Earth Science, 3, 2224-3216.

[17]   Vander-Velpen, B.P.A. (2004) WinRESIST Version 1.0 Resistivity Depth Sounding Interpretation Software. M.Sc Research Project, ITC, Delft, the Netherland.

[18]   Henriet, J.P. (1976) Direct Application of the Dar Zarrouk Parameters in Groundwater Surveys. Geophysical Prospecting, 2, 344-353.
http://dx.doi.org/10.1111/j.1365-2478.1976.tb00931.x

[19]   Smith, W.H.F. and Wessel, P. (1990) Gridding with Continuous Curvature Splines in Tension. Geophysics, 55, 293-305.
http://dx.doi.org/10.1190/1.1442837

[20]   Olayinka, A.I., Amidu, S.A. and Oladunjoye, M.A. (2004) Use of Electromagnetic Profiling and Resistivity Sounding for Groundwater Exploration in the Crystalline Basement Area of Igbeti, Southwestern Nigeria. Global Journal of Geological Sciences, 2, 243-253.
http://dx.doi.org/10.4314/gjgs.v2i2.18701

[21]   Akintorinwa, O.J. (2015) Groundwater Potential Assessment of Iwaro-Oka, SW Nigeria Using Geoelectric Parameters. British Journal of Applied Science & Technology, 6, 364-377.
http://dx.doi.org/10.9734/BJAST/2015/14584

[22]   Omosuyi, G.O. (2010) Geoelectric Assessment of Groundwater Prospect and Vulnerability of Overburden Aquifers at Idanre, Southwestern Nigeria. Ozean Journal of Applied Science, 3, 19-28.

[23]   Worthington, P.R. (1977) Geophysical Investigations of Groundwater Resources in the Kalahari Basin. Geophysics, 42, 838-849.
http://dx.doi.org/10.1190/1.1440751

[24]   Olayinka, A.I. and Olorunfemi, M.O. (1992) Determination of Geoelectric Characteristics in Okene Area and Implications for Borehole Siting. Journal of Mining and Geology, 28, 403-411.

[25]   Adelusi, A.O., Ayuk, M.A. and Oyedele, A.A. (2004) Hydrogeophysical Analysis of Owode Area around Oba-Ile near Akure, SW Nigeria. African Journal of Development Studies, 4, 11-14.

[26]   Mallam, A. (2004) Fresh Basement: Revealed from Resistivity Method. Zuma Journal of Pure and Applied Sciences, 6, 6-9.

[27]   Wright, E.P. (1992) The Hydrogeology of Crystalline Basement Aquifers in Africa. Geological Society of London, Special Publications, 66, 1-27.
http://dx.doi.org/10.1144/GSL.SP.1992.066.01.01

[28]   Oyedele, E.A.A. and Olayinka, A.I. (2012) Statistical Evaluation of Groundwater Potential of Ado-Ekiti, Southwest Nigeria. Transnational Journal of Science and Technology, 2, 110-127.

[29]   Shemang Jr., E.N. (1993) Groundwater Potentials of Kubanni River Basin, Zaria, Nigeria from DC Resistivity Study. Water Resources, 4, 36-42.

[30]   Aboh, H.O. and Osazuwa, I.B. (2000) Lithological Deductions from Regional Geoelectric Investigation in Kaduna, Kaduna State Nigeria. Nigerian Journal of Physics, 12, 1-7.

[31]   Olorunfemi, M.O. and Fasuyi, S.A. (1993) Aquifer Types and the Geoelectric/Hydrogeologic Characteristics of Part of Central Basement Terrain of Nigeria (Niger State). Journal of African Earth Sciences, 16, 309-317.
http://dx.doi.org/10.1016/0899-5362(93)90051-Q

[32]   Bala, A.E. and Ike, E.C. (2001) The Aquifer of the Crystalline Basement Rocks in Gusau Area, North-Western Nigeria. Journal of Mining and Geology, 37, 177-184.

[33]   Omosuyi, G.O., Ojo, J.S. and Enikanselu, P.A. (2003) Geophysical Investigation for Groundwater around Obanla-Obakekere in Akure Area within the Basement Complex of South-Western Nigeria. Journal of Mining and Geology, 39, 109-116.

[34]   Olayinka, A.I., Akpan, E.J. and Magbagbeola, O.A. (1997) Geoelectric Sounding for Estimating Aquifer Potential in the Crystalline Basement Area around Shaki, Southwest Nigeria. Water Resources, 8, 71-81.

[35]   Olorunfemi, M.O., Ojo, J.S. and Akintunde, M.O. (1999) Hydrogeophysical Evaluation of the Groundwater Potentials of the Akure Metropolis. Journal of Mining and Geology, 35, 207-228.

[36]   Oladapo, M.I., Mohammed, M.Z., Adeoye, O.O. and Adetola, B.A. (2004) Geoelectrical Investigation of the Ondo State Housing Corporation Estate, Ijapo Akure, Southwestern Nigeria. Journal of Mining and Geology, 40, 41-48.
http://dx.doi.org/10.4314/jmg.v40i1.18807

[37]   Oladapo, M.I. and Akintorinwa, O.J. (2007) Hydrogeophysical Study of Ogbese, Southwestern, Nigeria. Global Journal of Pure and Applied Sciences, 13, 55-61.
http://dx.doi.org/10.4314/gjpas.v13i1.16669

[38]   Abiola, O., Enikanselu, P.A. and Oladapo, M.I. (2009) Groundwater Potential and Aquifer Protective Capacity of Overburden Units in Ado-Ekiti, Southwestern Nigeria. International Journal of Physical Sciences, 4, 120-132.

[39]   Akintorinwa, O.J. and Abiola, O. (2012) Comparison of Schlumberger and Modified Schlumberger Arrays VES Interpretation Results. Research Journal in Engineering and Applied Sciences, 1, 190-196.

[40]   Olorunfemi, M.O. and Okhue, E.J. (1992) Hyrogeologic and Geologic Significance of a Geoelectric Survey at Ile-Ife, Nigeria. Journal of Mining and Geology, 28, 242-350.

[41]   White, C.C., Huston, J.T.F. and Baker, R.D. (1988) The Victoria Province Drought Relief Project 1. Geophysical Sitting of Boreholes. Groundwater, 26, 309-316.
http://dx.doi.org/10.1111/j.1745-6584.1988.tb00394.x

[42]   Lenkey, L., Hamori, Z. and Mihalffy, P. (2005) Investigating the Hydrogeology of a Water-Supply Area Using Direct-Current Vertical Electrical Sounding. Geophysics, 70, 1-19.
http://dx.doi.org/10.1190/1.2000288

[43]   Ojo, A.O., Oyelami, C.A. and Adereti, A.O. (2014) Hydro-Geochemical and Geophysical Study of Groundwater in the Suburb of Osogbo, South Western Nigeria. Journal of Earth Science & Climatic Change, 5, 205.

[44]   Ariyo, S.O., Omosanya, K.O. and Oshinloye, B.A. (2013) Electrical Resistivity Imaging of Contaminant Zone at Sotubo Dumpsite along Sagamu-Ikorodu Road, Southwestern Nigeria. African Journal of Environmental Science and Technology, 7, 312-320.

 
 
Top