Estimating geohydraulic parameters, protective strength, and corrosivity of hydrogeological units: a case study of ALSCON, Ikot Abasi, southern Nigeria

Abstract

The study area, characterized by prolific surface and groundwater repositories, is faced with the challenges of surface and groundwater pollutions. These pollutions need good management practices to avoid waterborne diseases. In an attempt to solve this problem, the integration of vertical electrical sounding (VES) method with laboratory analysis of borehole water was undertaken to size up the contour of groundwater geohydraulic parameter distributions and their dispositions. These Parameters are fraught with information concerning contaminant plume. Aquifer repositories characterized by fine to coarse sands have resistivity ranging from 166.3-2332.5 Ωm, delineated through the use of manual and electronic processing aided by software packages such as WINRESIST and SURFER. Thickness ranged from 2.6-170.3 m. Using the VES results and water resistivity, porosities were determined using Archie's model. Estimated porosities were employed in the Kozeny-Carman-Bear's Model to estimate the hydraulic conductivity for all the VES stations and good fits were obtained with pump test results. The K values were combined with Dar Zarrouk parameters to infer the hydraulic transmissivity. The results indicate that fractional porosity varies from 0.102 to 0.198. The hydraulic conductivities ranged from 7.48 × 10 −6 to 5.33 × 10 −5 m/s, while the transmissivity values vary between 7.938 × 10 −5 and 3.389 × 10 −3 m 2 /s. The tortuosity of the aquifer also varies from 1.12 to1.35 while the conductance of aquifer per day varies from 259 to 15,575 μS/day. The hydrogeological units are generally prone to interaction with brackish/saline water from the Imo River and corrosion from surface sources due to the high permeability of the layers surrounding the geometries of water repositories. The ranges of parameters estimated are consistent with literatures for studies conducted in other areas with similar geomaterials, therefore indicating the efficacy of the method.

Assessment of spatial distrilbution of porosity and aquifer geohydraulic parameters in parts of the Tertiary – Quaternary hydrogeoresource of south-eastern Nigeria

“…On the other hand, TR and T were noticed to relate linearly. The linearly dependent relation between TR and T has also been observed by Soupios et al (2007), Batte et al (2010) and Ibanga and George (2016).…”

“…Despite the fact that conventional approach employing surface electrical resistivity derived parameters is dominating many literatures at both international and local levels, other classical surface geophysical techniques like the self potential (SP), seismic refraction, ground penetration radar (GPR), time and frequency domain electromagnetic techniques, induced polarisation and so on in aquifer parameter quantification and spread mapping are also significantly gaining ground (Corwin, 1990;Slater, 2007;Kirsch, 2009;Jouniaux et al, 2009). The conversion of geophysical data, usually obtained by indirect procedures into its corresponding geological facies is often observed and as pointed out by Ibanga and George (2016), the absence of a functional relations linking the observed formation parameters with the grain size distribution and other facies properties of the formation relating to permeability directly has been a major factor debilitating against direct extraction of any needed input. Even with this, recent innovations in geophysical methodologies such as surface nuclear magnetic resonance (SNMR) technique and spectral induced polarisation (SIP) or enhancements in interpretational techniques employed in the analyses and interpretation of classical geophysical data have high prospects for upsetting the ambiguities imposed by direct information extraction (Yaramanci et al 1999;Sailhac et al, 2004;Vereecken et al, 2004;Jouniaux et al, 2009;Kirsch, 2009;Daigle and Dugan, 2011;Günther and Müller-Petke, 2012;Ikard et al, 2012;Jouniaux and Ishido, 2012;Kulessa et al, 2012).…”

Geophysical Assessment of Vulnerability of Surficial Aquifer in the Oil Producing Localities and Riverine Areas in the Coastal Region of Akwa Ibom State, Southern Nigeria

“…The BendeAmeki Group indicates the continued regressive phase. The survey area falls into the low-lying Benin Formation in southern Nigeria 15,16 . The drainage in mapped area is made possible by the Kwa River, cross rivers and Etim Ekpo tributaries 17 .…”

Geophysical exploration to estimate the surface conductivity of residual argillaceous bands in the groundwater repositories of coastal sediments of EOLGA, Nigeria

“…Assumption of the local geological setting may not always be appropriate and resources should be targeted on districts where problems can be solved. Qualitative interpretations are adequate in some situations but more rigorous field procedures and analytical techniques are needed to ensure that useful hydrogeological information is obtained (Carothers, 1986;Ibanga and George, 2016) In sediments, which conduct electronically, formation conductivity is related to the volume and conductivity of the water in earth materials. The groundwater conducts through its ions, and its conductivity, therefore, depends strongly on the total dissolved solids.…”