(searched for: doi:10.1016/j.heliyon.2020.e03327)
Concepts in Magnetic Resonance Part A, Volume 2021, pp 1-11; https://doi.org/10.1155/2021/5424865
Vertical electrical sounding and magnetic methods were carried out to assess groundwater potential in Adilo catchment, Kembata Tembaro Zone, South Nations, Nationalities and Peoples Regional Government, Main Ethiopian Rift. The data were acquired from eight VES points using Schlumberger electrode arrays with maximum half current electrode spacing ( AB / 2 = 500 ) and 253 magnetic data points were analyzed. The qualitative analysis of VES data was accomplished by using curves, apparent resistivity, and pseudodepths, and the quantitative interpretations of the VES data were constructed by the VES data using IPI-Res3, IPI2Win, and surfer software and constructing geoelectric section along with profiles and lithological information from the borehole and Geosoft interpretation was used for magnetic data. The VES results of the data revealed five geoelectric layers which differ in degree of fracturing, weathering, and formation. The upward continued magnetic field map anomaly to 560 m illustrated northwestern to the southwest; areas have a low magnetic anomaly. Examining the potential aquifer of profile one’s geoelectric section, the horizons of layer four were better potential aquifers as the highly fractured and weathered ignimbrite zone of layer five of VES13 was 219 m deeper than the depths of the other VES points, and along with profile two geoelectric sections, the horizon of layer four VES23 layer five has the lowest resistivity with large thickness at a depth of 253 m. Thus, the low resistivity and the large thickness of these formations are an indication of the high yield of groundwater potential in the study area.
Results in Geophysical Sciences, Volume 5; https://doi.org/10.1016/j.ringps.2021.100012
In this study, eighteen (18) vertical electrical sounding (VES) data points were located in the Federal Capital Territory (FCT), Abuja, Nigeria with ABEM Terrameter using Schlumberger array to delineate potential groundwater development areas. Groundwater flow direction map was produced using the elevation of the water level from sea level with GIS Arc/Info Point coverage. The investigated areas have four geoelectric sections, categorized as topsoil, clay, fractured/weathered basement, and fresh basement. The groundwater is mainly confined in the fractured/weathered basement. It generally flows from NW to SE, but this flow is not steady. It has been obstructed and reoriented towards the south, whereas some portion flows towards the northern parts of the aquifer system peradventure due to the variation in aquifer depth from place to place. Out of the 18 VES points, 9 points located around the NE and SE peripherals of the study area have groundwater development potentials at depths ranging from 40 - 80 m and aquifer thickness of 25 – 65 m, characterized by resistivity values that varied from 80 – 680 Ωm, whilst the other nine in the SW and central parts do not show promising groundwater development potentials because they lack fractured/weathered zones. The northern and SE zones, which comprise areas such as Bwari, Kuje, Idu CITEC, Sherete, and GTSSC are the preferred targets for water well drilling than the southern zone. However, other communities including Gwagwalada and Gugugu in the southern zone also offer promising groundwater potentials.
Published: 1 February 2021
IOP Conference Series: Earth and Environmental Science, Volume 655; https://doi.org/10.1088/1755-1315/655/1/012069
A microstudy of soil physical properties in combination with geoelectric delineation were adopted for the evaluation of groundwater contamination prospect from leachate migration at Bowen University dumpsite location. Samples of soil were collected from five different locations, with five locations within the dumpsite and one control sample which is 200 m far away from the dumpsite locations. A core sampler which is attached to the soil auger is used to obtain each sample within 60 cm depth. Each sample is collected into a sample bag and properly labeled for laboratory analysis. Schlumberger electrode configuration was employed for the survey spread to delineate total of four (4) Vertical electrical sounding (VES) points with electrode spacing varying 60 to 100 m. This was done to obtain resistivity, thickness and depth within the dumpsite location. The results of the average value of the soil properties between the control and the dumpsite are compared such that the soil properties for control site reveal a bulk density (BD) of 1.45 g/cm3, particle density (PD) of 2.63 g/cm3 and porosity (PO) of 44.90%, respectively. Whereas, the mean soil properties of the dumpsite show that BD is 1.35 g/cm3, PD is 2.93 g/cm3, and PO is 54.07%, respectively. This signifies that the control location has high BD, low PD and low PO, while the dumpsite reveals an inverse of the control results. Also, the results from the interpreted VES data reveal the prospect of migration of contaminants from the topsoil to the alluvium, which could further percolate to the aquifer with time. It could be concluded that groundwater contamination is feasible within the study area, since an alluvium and porous soils could permit leachate migration to the aquifer.
Published: 1 February 2021
IOP Conference Series: Earth and Environmental Science, Volume 655; https://doi.org/10.1088/1755-1315/655/1/012092
The environmental monitoring of radon contents in some bottled and sachet water were carried out, with the aid of an active radon device (RAD7) made by Durridge, USA. This study is aimed to determine the level of radon in selected bottled and sachets water in major market in Ile-Ife, with a view to establishing the health risks that could arise in consumption of the water. The results obtained in this study show that all the water samples were safe for consumption without any health implication from radiological point of view.
MethodsX, Volume 8; https://doi.org/10.1016/j.mex.2021.101215
In the Karumeniyar river basin, the groundwater demand increases for irrigation, industrial and larger per capita needs, and the recent year's groundwater table is drastically falling due to both natural and anthropogenic activities. In this context, a study on geophysical vertical electrical sounding (VES) using Schlumberger configuration has been carried out across 72 locations in the Karumeniyar river basin to demarcate the subsurface geoelectrical parameters and to identify the groundwater potential zone along with aquifer protective capacity. The acquired data were inverted using the 1D (resistivity variation with respect to depth) inversion approach IPI2Win demonstrated the presence of three to six subsurface geoelectrical layers in the study area with H type sounding curve being dominant. Furthermore, the deciphered result from VES is cross-validated with lithology data of four wells in the study area. Based on the interpreted results the parameters such as longitudinal conductance, overburden thickness, reflection coefficient and basement resistivity were calculated. It revealed that 36 VES location signifies good to moderate aquifer protective capacity. According to the reflection coefficient value and overburden thickness, the basin was divided into four distinct groundwater potential zones as high (42%), medium (38%), low (15%) and very low (5%). The inverse Distance Weighting (IDW) interpolation method is adopted to generate the spatial distribution maps in ArcGIS environment. The findings of the present study provide the vital geo-database for groundwater potential zones in the Karumeniyar river basin and have important implications for designing, intendance and management of sustainable groundwater resources.
Open Geosciences, Volume 12, pp 376-389; https://doi.org/10.1515/geo-2020-0100
A seismic wave is released when there is sudden displacement on a fault plane. The passage of this wave along the fault plane or within the lithosphere could result in ground shaking or vibration at the surface of the Earth. To provide a geophysical explanation to this phenomenon, the high-resolution aeromagnetic data of the sedimentary terrain and part of the Basement Complex of Southwestern Nigeria were processed and interpreted to provide fault architecture of the area, which could serve as conduit for the passage of seismic energy in the study area. High-resolution aeromagnetic data along the Lagos–Ore axis are processed for fault mapping in the study area. The reduced-to-equator (RTE) residual aeromagnetic data used were enhanced using the total horizontal derivative (THD) and upward continuation (UC) filtering techniques on Oasis Montaj 6.4.2 (HJ) software. The resultant maps were overlaid and compared with the plotted RTE residual maps for relevant interpretations. Varying signatures of magnetic anomalies are grouped into high (57.9–89.1 nT), intermediate (38.2–57.9 nT), and low (4.0–38.2 nT) magnetic intensities, which are associated with contracting basement rocks features. The obtained lineaments from the THD reveal areas of various deformations such as brittle, which is associated with faults/fractures, and ductile deformation, which is associated with folds of geological features. The faults, as depict by the UC map, reveal different depth ranges of 500–2250 m at the western side and 1,500–1,250 m at the northwestern area of the study. Since it has been on record that September 11, 2009, earth tremor of magnitude 4.4, with the epicenter at Allada, Bennin Republic, 128 km west of Lagos, Nigeria occurred within the study area, it can be inferred that the established geologic fault architecture could be responsible for the hazard and be part or synthetic to the Ifewara-Zungeru fault in Nigeria.