Comparison of underground resistivity in parts of Odi- Sagbama Local Government and Eastern parts of Yenagoa, Bayelsa State, Niger Delta, Nigeria

The need to compare the underground Resistivity in Odi-Sagbama Local Government area and eastern parts of Yenagoa, Bayelsa State, Nigeria, to help individual, government or private agency to make a choice of location for the infrastructural developmental stride of the area necessitated this research. A total of eight Vertical Electrical Soundings (VES) were conducted in each side of the study area using Schlumberger array and Abem Terrameter (SAS 1000) to acquire the data. Maximum electrode spread of 1000m was used in all the sixteen VES stations occupied and then a RESIT computer program employed to process the acquired resistivity sounding data. Seven HA resistivity curves (VES 1-6 and 8) and one QH in VES 7 were observed in Odi-Sagbama side while at eastern side of Yenagoa, the curves vary significantly: HA (VES 9), KHA (VES 10), AHK (VES 11), QKH (VES 12), HA(14), HK (VES 13, 15 ), and HKA (VES 16).This indicates more stratification in eastern parts of Yenagoa. In each side, the topsoil resistivity is less than 100Ωm in five stations and above100 Ωm in three. The resistivities encountered are lower in Odi-Sagabama than eastern parts of Yenagoa as the lowest and the highest are 5.2 Ωm and 542.4 Ωm in the former and 10.2 Ωm and 922.1 Ωm in the latter.The average resistivity of the Aquifers and average depth of Water Tablein the area (Odi-Sagbama)are 265.2 Ωm and 71.06m respectively while they are 266.46 Ωm and 42.76m respectively in eastern Yenagoa. Generally, lithologyen countered are Clay and Sand which are present in all the layers in different forms and at different depths, Clay being the dominant. Except in layer four, the lithology are the same on the two sides of the study area but are at different depths and thicknesses.