Evaluation of Groundwater Potential in Takum Metropolis, North East Nigeria, Using the Electrical Resistivity Method.

Abstract

Vertical electrical sounding (VES) were taken at twelve (12) electrode equipped stations using the Schlumberger design, with spacing of  =100m. The aim of the study is obtaining the geophysical parameters and hydrological conditions of the subsurface of the study area. Electrical resistivity was used to measure the depth dependent resistivity variations of the subsurface in groundwater investigation. Software programs Interpex IX1-D and surfer 12were used to examine the data. Two unique curve types can be seen in the examined result which are Q- type 8.3% and H-type have 91.7%. Iso-resistivity maps of  = 70m and 100 m were produced. The anomaly was seen at Akpela in the northwest, Awuhe in the southwest and two minor anomalies are found in the southeast and northeast, hard resistive rocks are indicated in the research areas portion that corresponds to the 3-D model. The area is underlain by three to four geologic sequences, consisting of top soil, fractured/weathered basement, and fresh basement, according to a geo-electric  section. Sand and silty minerals make up the topsoil, and they have resistivity and thickness values that range from 391 – 617 Ωm and 1.5 – 6.8 m. The second layer which is basically silty materials and fractured weathered granite consist of highly fracture/weathered basement with resistivity measurements between 15 – 189 Ωm and a thickness of 4 – 37 m. This layer has an appreciable thickness and can be consider to be water bearing zones. Fresh basement has resistivity values of 1878 – 7463 Ωm with infinite depth. Longitudinal conductance for twelve (12) VES points were utilized to determine the capacity to defend against overburden. Two VES points have excellent capabilities, six (6) have moderate, three (3) have weak and two (2) have poor protective capacity. Transverse resistance values range from 1373.90-6397.08 Ωm² with an average value of 3712.08 Ωm².