Application of multi-criteria decision analysis in prediction of groundwater resources potential: A case of Oke-Ana, Ilesa Area Southwestern, Nigeria

Abstract

Groundwater Potential of Oke-Ana area southwestern Nigeria have been evaluated using the integration of electrical resistivity method, remote sensing and geographic information systems. The effect of five hydrogeological indices, namely lineament density, drainage density, lithology, overburden thickness and aquifer layer resistivity on groundwater occurrence was established. Multi-criteria decision analysis technique was employed to assign weight to each of the index using the concept of analytical hierarchy process. The assigned weight was normalized and consistency ratio was established. In order to evaluate the groundwater potential of Oke-Ana, sixty-seven (67) vertical electrical sounding points were occupied. Ten curve types were delineated in the study area. The curve types vary from simple three layer A and Htype curves to the more complex four, five and six layer AA, HA, KH, QH, AKH, HKH, KHA and KHKH curves. Four subsurface geo-electric sequences of top soil, weathered layer, partially weathered/fractured basement and the fresh basement were delineated in the area. The analytical process assisted in classifying Oke-Ana into, low, medium and high groundwater potential zones. Validation of the model from well information and two aborted boreholes suggest 70% agreement.

Application of Geophysical Borehole Logs For Aquifer Characterization in Coastal Environment of Lagos, Southwestern Nigeria

“…For the consistency and hence usability of the weights, the consistency ratio must lie within the acceptable limit of less than or equal to ten percent (≤10%) (Saaty, 1980(Saaty, , 1990(Saaty, and 1994. The procedure for determining the consistency ratio had been discussed in 2012, Adiat et al;2013, Akinlalu et al;2017 and Adiat et al;2018. In the third step, the GALDIT Index is then obtained by computing the individual indicator scores and summing them using the following expression:…”

Modeling of geoelectric parameters for assessing groundwater potentiality in a multifaceted geologic terrain, Ipinsa Southwest, Nigeria – A GIS-based GODT approach

“…The pair-wise comparison technique represents a theoretically founded basis to compute weights indicating the relative importance of the criteria. The uniqueness of this model's theory application in environmental decision making process is that of its capability to computing the level of consistency in the pairwise comparison matrices via applying the model's sound mathematical basic equations as detailed in the studies of Zhou and Chen (2014), Mogaji and Lim (2016) and Akinlalu et al (2017). The prepared Pair-Wise comparison Matrices for the selected GPCFs is shown in Table 4.…”

“…groundwater potentiality conditioning factors (GPCFs) often served as input indices synthesized for groundwater potentiality zones prediction in the investigated areas (Adiat et al, 2012;Jha et al, 2010). To mention few of the commonly used GPCFs input indices are lithology, drainage pattern, lineament density, soil and topographic slope, geoelectrical parameters (lithology layer's resistivity and thickness) etc (Akinlalu et al, 2017;Mogaji and Lim, 2016;Adiat et al, 2013). The combination of those used GPCFs for the potential zones modeling was effectively carried out through exploring the potential of the MCDA -AHP systemic approach.…”

Investigation of the influence of lineaments, lineament intersections and geology on groundwater yield in the basement complex terrain of Ondo State, Southwestern Nigeria

“…Basement aquifers constitute relevant sources of water in the hard rock terrain of Ondo State in which groundwater occurs mainly in fractured zones, with or without saturated weathered zones (Olorunfemi and Olorunniwo 1985;Olorunfemi 1990;Olorunfemi et al 1991;Olorunfemi and Okhue 1992;Idornigie and Olorunfemi 1992;Olorunfemi and Fasuyi 1993;Olorunfemi 2007;Ekwe et al 2010;Bayowa et al 2014;Akinlalu et al 2017). However, the development of crystalline bedrock aquifers is highly complex, and groundwater occurrence is spatially variable due to many factors (Satpathy and Kanungo 1976;Mabee et al 1994;Mabee 1999;Mabee et al 2002;Ojo et al 2015;Aladejana et al 2016).…”

“…However, the development of crystalline bedrock aquifers is highly complex, and groundwater occurrence is spatially variable due to many factors (Satpathy and Kanungo 1976;Mabee et al 1994;Mabee 1999;Mabee et al 2002;Ojo et al 2015;Aladejana et al 2016). Though tectonic history, geomorphology and climatic conditions play prominent role in the development of weathered and fractured aquifer systems, in this kind of terrain, water percolation and accumulation is essentially controlled by fractures and other rock discontinuities (Lattman et al 1964;Siddiqui and Parizek 1971;Edet et al 1994;Edet 1996;Sander 1997;Taylor andHoward 2002, Anifowose et al 2012;Akinlalu et al 2017). Therefore, knowledge of some surficial features such as lineament (originated possibly by faults, fractures, joints, foliation, etc.)…”