Vol.:(0123456789) 1 3 Modeling Earth Systems and Environment https://doi.org/10.1007/s40808-020-01030-2 ORIGINAL ARTICLE Modelling aquifer parameters using surficial geophysical techniques: a case study of Ovwian, Southern Nigeria R. E. Iserhien‑Emekeme 1  · M. O. Ofomola 1  · O. Ohwoghere‑Asuma 2  · F. I. Chinyem 2  · O. Anomohanran 1 Received: 29 July 2020 / Accepted: 17 October 2020 © Springer Nature Switzerland AG 2020 Abstract Vertical electrical sounding (VES), pumping test and grain size distribution techniques have been used to model the hydraulic parameters in Ovwian, Nigeria. Twenty-two depth soundings were carried out with a maximum current electrode separa- tion of 400 m to delineate the aquifer layers while the pumping test and grain size distribution procedures were conducted by drilling two boreholes where thirteen representative soil samples were collected at an interval of 3.048 m. The field data obtained from the resistivity sounding were modelled using the Win Resist software and the results when correlated with borehole log identified five geoelectric units made up of the topsoil, clayey sand, sandstone, fine grain sand and coarse grain sand. The sands of the third and fourth geologic layers constitute the aquiferous units with depth which varied between 6 and 42 m while the aquifer resistivity ranged between 100 and 2100 Ωm. The pumping test was analysed using the Copper Jacob method and the results revealed that the hydraulic conductivity and transmissivity of the aquifer from the reference well are 30.467 m/day and 495.072 m 2 /day, respectively. These results together with results from the vertical electrical sound- ings were used to model the hydraulic conductivity and transmissivity values for the area. This showed that the hydraulic conductivity of the area ranged from 28.595 to 38.435 m/day, with a mean value of 30.757 m/day while the transmissivity ranged from 185.697 to 1310.636 m 2 /day, with a mean of 495.752 m 2 /day. The grain size distribution analysis also revealed the hydraulic conductivity value of 1.46–171.94 m/day with an average of 38.880 m/day, while transmissivity ranged from 23.725 to 2794.025 m 2 /day with an average values of 631.738 m 2 /day. The close approximations of the results revealed the reliability of the VES, pumping test and grain size distribution analysis in the estimation of aquifer hydraulic parameters for groundwater resource development. Analyses of the results obtained in this study suggest that the aquifer is prolific and highly permeable with a high degree of rechargeability. Keywords Grain size distribution · Hydraulic conductivity · Aquifer · Vertical electrical sounding · Transmissivity · Ovwian Introduction The sustainable development of every nation is strongly dependent on the supply of clean water to its citizens (Theeba et al. 2015). However, the increase in the demand for potable water by the rising population of the people in Ovwain, Nigeria and the associated need for the proper man- agement and protection of the water resource have been a major problem in the study area. This concern has necessi- tated the need to carry out a study to obtain accurate infor- mation on the aquifer type, depth to groundwater, extent of the alluvial aquifer system and the characterization of the hydraulic properties of the aquifer in the area. Many geophysical techniques are available and have been used to investigate the groundwater potential of a given location. These methods include Surficial geophysics which refers to the way in which the unconsolidated sedi- ment and groundwater potential of the earth is investigated. This is investigated using geophysical techniques which include seismic (Alhassan et al. 2018), electrical resistivity (Oguama et al. 2019; Anomohanran et al. 2020; Ekanem 2020), magnetic (Teatini et al. 2011), GIS (Chakrabortty et al. 2018) and remote sensing (Boufala et al. 2019). Of all * M. O. Ofomola ovirimerrious@yahoo.com 1 Department of Physics, Delta State University Abraka, Abraka, Nigeria 2 Department of Geology, Delta State University Abraka, Abraka, Nigeria