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1
Tsepav, Matthew Tersoo, Aliyu Yahaya Badeggi, Obaje Nuhu George, Usman Yusuf Tanko, and Ibrahim Samuel Ibbi. "On the Use of Electrical Resistivity Method in Mapping Potential Sources and Extent of Pollution of Groundwater Systems in Lapai Town, Niger State, Nigeria." Journal of Physics: Theories and Applications 5, no. 1 (March 30, 2021): 18. http://dx.doi.org/10.20961/jphystheor-appl.v5i1.51563.
Повний текст джерелаАнотація:
<p>Electrical resistivity method employing the Schlumberger array was used to occupy forty four (44) vertical electrical sounding points in Lapai town with the aim of determining the depth to aquifers, aquifer thicknesses and aquifer protective capacity. The G41 Geotron resistivity meter was used in obtaining the apparent resistivity data which was processed using Interpex 1XD resistivity interpretation software. The results revealed four lithologic sections which include top lateritic soil, sandy clay, fractured basement and fresh basement. Both confined and unconfined aquifers were identified within the area, with four classes of aquifer proactive capacities as high, moderate, weak and poor. While the aquifer at VES 20 was highly protected, twenty other aquifers were moderately protected, eight others had weak protection and fifteen aquifers were poorly protected. The aquifers were generally of good thicknesses and at varying reasonable depths, making them good reservoirs of water in appreciable quantity. The average aquifer thickness was estimated to be 48.36m while the average depth to aquifers was estimated to be 56.68m.</p>
2
Akanbi, Olanrewaju Akinfemiwa, and Moshood ‘Niyi Tijani. "Sustainability and Conceptual Groundwater Hydraulic Models of Basement Aquifers." Materials and Geoenvironment 66, no. 2 (June 1, 2019): 87–98. http://dx.doi.org/10.2478/rmzmag-2019-0016.
Повний текст джерелаАнотація:
AbstractGroundwater flow of the basement terrains of the Ibarapa region was studied by carrying out pumping test and measurement of borehole inventory. The view was to identify the associated aquifer systems from the time-drawdown curves, quantify the estimable hydraulic properties and develop hypothetical models for the understanding of the groundwater flow in the area underlain by diverse crystalline bedrocks. Three aquifer types were identified namely, dual, leaky and regolith. The yield of groundwater in dual and leaky aquifers that dominated terrains underlain by amphibolite and gneisses was sustainable, but the discharge of regolith aquifers mainly associated with migmatite and granite terrains declined at late pumping stage. The transmissivities of the dual and leaky aquifers were between 2.02 and 11.65 m2/day, while those of regolith aquifers were mostly less than 1.00 m2/day. The average aquifer transmissivities in m2/day by bedrocks were: 6.85, 2.57, 0.76 and 1.72, correspondingly. The inter-relationships between transmissivities and groundwater discharge showed diverse aquifer representations, from sustainable high-yielding to unsustainable low-yielding types. Conscientious effort is, therefore, required for well construction in the area.
3
Bello, Rereloluwa, and Toluwaleke Ajayi. "Geoelectric evaluation of groundwater potential within sunshine garden estate, akure southwestern Nigeria." International Journal of Physical Research 7, no. 2 (July 22, 2019): 61. http://dx.doi.org/10.14419/ijpr.v7i2.29172.
Повний текст джерелаАнотація:
The Vertical Electrical Resistivity surveys in the Sunshine Garden Estate have contributed to a better understanding of the basement complex of Southwestern Nigeria. Nine (9) vertical electrical sounding (VES) using the Schlumberger electrode array were interpreted and the results shows three (3) subsurface geoelectric layers within the study area. These are the weathered layer, topsoil, fresh/fractured basement. Groundwater pockets such as fractured zones, valley fills/basement depressions, and weathered zones were delineated in the study area. Weathered/partially weathered layer and weathered basement/fractured basement were the two major aquifer mapped out and these aquifers are characterized by thick overburden, found within basement depressions. The groundwater potential of the study area was zoned into low, medium and high potentials. Zones where the overburden thickness (which constitutes the main aquifer unit) is greater than 13m and of low clay composition (average resistivity value between 200 - 400Ωm) are considered zones of high groundwater potential. Area where the thickness of the aquifer ranges from 11-13m with less clay composition are considered to have medium groundwater potential and the areas where the thickness of the aquifer is less than 11m are considered to have a low groundwater. The VES station underlained by high and medium groundwater potential zones are envisaged to be viable for groundwater development within the area.
4
Subedi, B., T. Kitaoka, and J. Kiyono. "3D stratigraphic modelling of the Bangkok basin using Kriging on borehole data." IOP Conference Series: Earth and Environmental Science 851, no. 1 (October 1, 2021): 012014. http://dx.doi.org/10.1088/1755-1315/851/1/012014.
Повний текст джерелаАнотація:
Abstract The Lower Central Plain of Thailand has a deep and highly irregular basement filled with complex layers of alluvial sandy soil and deltaic clay or silt. The Bangkok Metropolitan region with its high level of infrastructure development is located in this plain. With high population density, the problem of land subsidence is critical. This study uses borehole data and the Kriging method to interpolate the data. A detailed 3D stratigraphic model of the basin is presented and several cross sections along two directions. Seventeen layers and the points used for modelling each layer are presented. The model shows eight aquifers in the Bangkok basin, lying between eight layers of clay, and a bottom layer above the basement. The bottom of the lowest aquifer of the Bangkok aquifer system is 610 m deep. The basement extends down to a depth of more than 2000 m in some places. Our 3D model, which extends to the basement, is of interest for mining and site-specific seismic risk analysis. Moreover, our results can be very useful for groundwater and land subsidence studies.
5
Shuaibu, A. M., M. L. Garba, and I. Y. Abubakar. "Aquifer characteristics and groundwater flow system in a typical basement complex and Gundumi formation northwest, Nigeria." Bayero Journal of Pure and Applied Sciences 15, no. 1 (December 9, 2022): 26–37. http://dx.doi.org/10.4314/bajopas.v15i1.4.
Повний текст джерелаАнотація:
Aquifer performance was tested in 280 locations of the study area to assess the hydraulic characteristics of the various aquifers, potential yield from the flowing boreholes of both hard rocks and sedimentary formation underlain Zamfara State Northwestern, Nigeria. Pumping test result were subjected to standard methods of Jacob’s and modified Theis equation for evaluation of aquifer parameters such as hydraulic conductivity (K), Transmissivity (T), Specific capacity and others. The results show that characteristic of areas underlain by crystalline rock units, especially migmatite, variably migmatized gneiss, schists and granites are characterized by thin/shallow overburden unit of usually less than 10m. In such settings the borehole depth varies from 38 to 78m while saturated thickness varies from 8 to 20m below ground level, with average yield of 44.1m3/day. Hydrogeological parameters obtained from pumping test analysis within the basement rock units revealed aquifer transmissivity (T) values which range from 0.14 to 141.23m2/day, with an average of 12.85m2/day. This implies aquifers of negligible to high potentials. The hydraulic conductivity (K) values vary from 5.0 x 10-2m/day and 8.8 x 10-1m/day with an average of 2.2 x 10-1m/day. The implication of these results is that the aquifers of the basement rock units cannot provide sufficient water for both domestic and agricultural needs of the area. However, Sixty-eight (68) analyzed borehole data set within Gundumi Formation, revealed the average discharge rate of 116.8m3/day. This formation shows the highest water discharge within the study area. The average penetration depth of 65m was achieved. The hydraulic conductivity of this aquifer revealed average value of 5.7 × 10-1m/day. This implies high permeability of aquifer system, which is typical of sedimentary formation of this nature. Transmissivity (T) revealed an average value of 38.89m2/day, which indicate high rate of water flow through the entire aquifer medium of this formation. The geospatial analysis of yield from the wells indicate excellent groundwater potential around the western part of the study area.
6
Kafando, Moussa Bruno, Mahamadou Koïta, Mathieu Le Coz, Ousmane Roland Yonaba, Tazen Fowe, Cheick Oumar Zouré, Moussa Diagne Faye, and Babacar Leye. "Use of Multidisciplinary Approaches for Groundwater Recharge Mechanism Characterization in Basement Aquifers: Case of Sanon Experimental Catchment in Burkina Faso." Water 13, no. 22 (November 12, 2021): 3216. http://dx.doi.org/10.3390/w13223216.
Повний текст джерелаАнотація:
In Burkina Faso, the basement aquifers represent a major asset in terms of quantity and quality, for both drinking and irrigation purposes for rural populations. They provide water resources that can guarantee the long-term needs of the populations, provided that a sustainable management policy for these resources is adopted. Yet, any groundwater resource management policy is necessarily linked to a better knowledge of aquifer recharge mechanisms, which is yet to be fully assessed in the Sahelian basement area. The objective of this study was to characterize the recharge mechanism within the experimental site of Sanon, located in the basement zone in Burkina Faso, using a coupling of hydrodynamic and chemical approaches. The hydrodynamic approach consisted of monitoring the spatial and temporal distribution of the piezometric levels of the aquifers along a north–south and east–west transect and determining soil infiltration capacity. The hydrochemical characterization of the aquifers was carried out through an analysis of groundwater samples from the concerned aquifers and daily tracing of the electrical conductivity of the aquifer water. The cross-analysis from the results of the implemented approaches shows a direct recharge mechanism through rainwater infiltration in the central valley, an indirect recharge mechanism in the lowlands, and a recharge mechanism by lateral transfers in the peripheral aquifers of the Sanon experimental catchment. The existence of a piezometric dome reveals in the central valley a zone of preferential recharge and water movement. The water of the central valley is the least mineralized with electrical conductivities below 100 µS/cm. This mineralization follows the direction of the water flow.
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Akpaneno, Aniefiok, and S. Abdulwahab. "GEOPHYSICAL INVESTIGATION OF GROUNDWATER CONTAMINATION USING DC RESISTIVITY TECHNIQUE AT THE MALE HOSTEL OF ISA KAITA COLLEGE OF EDUCATION DUTSIN-MA, KATSINA STATE, NIGERIA." FUDMA JOURNAL OF SCIENCES 4, no. 4 (July 13, 2021): 547–60. http://dx.doi.org/10.33003/fjs-2020-0404-643.
Повний текст джерелаАнотація:
A geophysical investigation involving Vertical Electrical Sounding (VES) using the Schlumberger array was carried out at the Isa Kaita College of Education specifically at the Male Hostel. The aim of the investigation is to explore the groundwater contamination of the area with the objectives: to determine the depth to basement of the study area, to determine the aquifer thickness, to determine the depth to aquifer, to determine the conductivity of the aquifer and to determine the thickness of topsoil and its variation in resistivity. A total of four (4) vertical electrical soundings were carried out using Schlumberger configuration. Terrameter signal averaging system (SAS) model 300 was the instrument used. The survey area is dominated by mainly four layers, namely: Topsoil, Weathered basement, fractured basement. The value of VES 03 and VES 04 have high electrical conductivities which likely shows they are contaminated, The topsoil resistivity along the profile ranges from approximately 1 to 154, The depth to basement (basement topography) Varies from 4.94 m to 7.59 m, The thickness of aquifer range from 1 m to 6.8 m. Therefore VES 02 has high Potential for groundwater because it has retaining capacity and good aquifer thickness and is therefore recommended for borehole establishment. It is recommended that the management of Isa Kaita College of Education should provide a concrete dumping site to avoid leaching of waste in ground thereby contaminating the groundwater.
8
Eissa, Mustafa A. "Application of Multi-Isotopes and Geochemical Modeling for Delineating Recharge and Salinization Sources in Dahab Basin Aquifers (South Sinai, Egypt)." Hydrology 5, no. 3 (August 4, 2018): 41. http://dx.doi.org/10.3390/hydrology5030041.
Повний текст джерелаАнотація:
The Dahab watershed comprises three aquifers; the alluvial Quaternary, the Early Cambrian sandstone, and the fractured Pre-Cambrian basement aquifers. The Dahab watershed is located in the southeastern part of the arid Sinai Peninsula, where low precipitation and groundwater over-exploitation deteriorate the groundwater quality in the alluvial coastal plain aquifer located downstream. Multi-isotopes including δ18O and δ2H, 87Sr/86Sr, δ81Br and δ11B coupled with groundwater geochemistry were utilized to assess the recharge source(s), water-rock interaction, and seawater mixing to aid sustainable groundwater management strategies. Br and Cl concentrations, used to measure groundwater salinity, were low in the upstream groundwater, while higher concentrations were observed in the deep drilled wells located downstream, in the main well field. The δ18O and δ2H isotopes were depleted in the upstream aquifers, but enriched in the shallow coastal aquifer, indicating slight evaporation and seawater intrusion. Higher mean values of 87Sr/86Sr and δ81Br were observed in the fresh groundwater from high in the watershed (87Sr/86Sr = 0.707716 and δ81Br = +2.05‰), while lower mean values were observed in the saline groundwater located downstream in the main well field (87Sr/86Sr = 0.706631 and δ81Br = +0.11‰). The cumulative mass balance mixing curves and the geochemical NETPATH model confirm the change of groundwater quality from the upper to lower watershed caused by the leaching and evaporation processes, as well as mixing with seawater. The corrected 14C age dating and stable isotopes show that the Quaternary and Pre-Cambrian basement aquifers contain modern groundwater, while the Early Cambrian aquifer holds paleo-groundwater, which has received considerable recharge from recent precipitation. The mixing ratiosin the Quaternary coastal aquifer range between 5% and 13% seawater to 95% and 87% fresh groundwater, respectively. These results indicate that future groundwater withdrawal must be well managed in order to limit further salinization. Groundwater withdrawal from the Quaternary coastal aquifer must be below the natural average recharge in order to be sustainable.
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Ademola, Iroye Kayode. "Effect of Down-Hole Lithological Variation on Water Bearing Capacity of Some Boreholes in Ilorin, Nigeria." Studia Universitatis Babeș-Bolyai Geographia 66, no. 2 (December 30, 2021): 5–23. http://dx.doi.org/10.24193/subbgeogr.2021.2.01.
Повний текст джерелаАнотація:
"Effect of Down-Hole Lithological Variation on Water Bearing Capacity of Some Boreholes in Ilorin, Nigeria. The paper attempts to explain the effect of downhole lithological variation on water bearing capacity of some boreholes in Ilorin Nigeria. Specifically, the study examined the lithological characteristics of the boreholes, assessed the variability in weathered overburden and analyzed the inter-relationships between lithology, hydrology and topography of the boreholes. Data used were extracted from twenty (20) borehole logs collected from the archive of Lower Niger Basin Development Authority in Ilorin. Information extracted from the borehole logs are: the number of lithological units intersected by each of the borehole and their depths, the nature of geological materials making up the lithological units and their moisture conditions. Information on coordinates and topographic heights of the boreholes are not given on the logs and those were collected from the field personally by the researcher using handheld GPS (Garmin GPS Channel 76 Model). The collected data were analyzed using descriptive statistics. Results reveal nine downhole lithological units with loamy and lateritic soil making up the first layer of lithology in 95% of the boreholes. Thickness of the top soil and the saprolite overlying the bedrock, has mean values of 4.2m and 11.3m respectively. Depth to water in the borehole ranged between 24.7 and 140m and with a mean value of 55.9m. Three (3) of the boreholes have two lenses of aquifer while the remaining seventeen (17) have one aquifer lens each. The three (3) boreholes with two aquifer lenses have their minor aquifers located within the saprolite. The main aquifer in most (65%) of the boreholes is located within the fractured basement while the remaining (35%) boreholes have their main aquifer located in the weathered basement. Correlation analysis revealed topographic elevation as one of the drivers of hydrology in the study area. Keywords: lithology, groundwater, saprolite, basement, topography. "
10
Jonker, B., and T. Abiye. "Groundwater potential of the eastern Kalahari region of South Africa." South African Journal of Geology 120, no. 3 (September 1, 2017): 385–402. http://dx.doi.org/10.25131/gssajg.120.3.385.
Повний текст джерелаАнотація:
Abstract An integrated approach involving geological, borehole data, hydrogeochemical and environmental isotope analyses was used to determine the groundwater potential of the eastern Kalahari region of South Africa, an area to the west of Mahikeng that stretches northward from the Orange River into Botswana. The total groundwater resource potential for the eastern Kalahari region of South Africa is estimated at 10127 Mm3/a, with the Kalahari Group aquifer showing the greatest potential, comprising 51% of the total resource. The storage capacity of the Kalahari Group aquifer (7130 Mm3) is also impressive, estimated to be more than twice that of the dolomite aquifer (2728 Mm3). Despite having such great potential, the aquifer is not actively recharged and is often associated with very saline water that is not suitable for human and livestock consumption. The limestone and dolomite aquifers of the Campbell Rand Subgroup, as well as the weathered granitic rocks of the Archaean basement, are considered as the most prospective water bearing formations, with a groundwater resource potential estimate of 1981 Mm3/a and 1845 Mm3/a, respectively. Aquifers with the least potential in the project area comprise the fractured basement rocks of the Kraaipan - Amalia greenstone belt, with a groundwater resource potential of 26 Mm3/a, and the fractured sedimentary rocks of the Asbestos Hills Subgroup, with a groundwater resource potential of 108 Mm3/a. The calculated groundwater storage and resource potential in the eastern Kalahari region of South Africa satisfies a large proportion of the water demand in the region.
11
Olatunji, Saminu, Ahmed Muyiwa Emiola, and Adewale Warith Adebisi. "AQUIFER VULNERABILITY EVALUATION IN SOUTHWESTERN NIGERIA FROM AHP-GODT MODEL USING GEO-ELECTRICAL DERIVED PARAMETERS." Jurnal Meteorologi dan Geofisika 22, no. 1 (October 8, 2021): 9. http://dx.doi.org/10.31172/jmg.v22i1.764.
Повний текст джерелаАнотація:
<em>The study aimed to determine the exposure levels of the subsurface aquiferous layers, owing to the alarming rate of contamination of the groundwater within 8.150 <sup>0</sup>N - 8.156 <sup>0</sup>N and 4.244 <sup>0</sup>E - 4.248 <sup>0</sup>E. Thus, aquifers' overlying layers, resistivity, and thickness anomalies were determined to generate an aquifer vulnerability map. A multi-criteria decision method of estimated Groundwater confinement, Overlying strata, Depth to Aquifer, and Topography index approach was implemented. Schlumberger's Vertical Electrical Sounding technique was implemented to acquire 30 Vertical Electrical Sounding points under a maximum half-current electrode separation (AB/2) of 65 m. IP2Win geophysical software packages were used to analyze the varying layer resistivity, depth, thickness, and also the sounding curves of the study area. The 2D model revealed a maximum of four geo-electric layers. The layers' resistivity and thickness ranges are clayey silt topsoil (52.5-1104 Ωm; 0.5-9.59 m), weathered layer (10.3-804 Ωm; 0.6-12.1 m), fractured basement (5.5-50832 Ωm; 6.7-18.1 m) and fresh basement (8.3-27348 Ωm; infinity m). On the Groundwater Overlying Strata Depth to Aquifer and Topography model scale, the area is generally characterized by the moderate vulnerability. Implying here is that aquifers have a moderate protective capacity in which the overlying strata above the aquifer are mostly impermeable layers (clay and silt) of high thickness and low porosity.</em>
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Deyassa, Gaddissa, Seifu Kebede, Tenalem Ayenew, and Tesfaye Kidane. "Crystalline basement aquifers of Ethiopia: Their genesis, classification and aquifer properties." Journal of African Earth Sciences 100 (December 2014): 191–202. http://dx.doi.org/10.1016/j.jafrearsci.2014.06.002.
Повний текст джерела
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Minnaar, R. C., and M. A. Dippenaar. "Hydrogeological characterisation of regional faults and dolerite dykes in the Precambrian Basement and Karoo Supergroup (Tete Province, Mozambique)." South African Journal of Geology 122, no. 3 (September 1, 2019): 343–56. http://dx.doi.org/10.25131/sajg.122.0023.
Повний текст джерелаАнотація:
Abstract Faults and dolerite dykes within Basement- and Karoo-aquifers in northern Mozambique may increase groundwater occurrence but may also be barriers to groundwater flow. Should observation boreholes drilled into regional and local faults as well as dykes show a response to aquifer testing, it would be deduced that these hydrogeological discontinuities are not barriers to groundwater flow. The approach adopted for this study included a sequential process involving data acquisition through a hydrogeological fieldwork programme consisting of geophysical surveys, borehole drilling, aquifer testing, and groundwater level monitoring. The Zambezi Border and geological contact faults were characterised by high variability in hydraulic properties. Aquifer testing resulted in drawdown in observation boreholes as well as a reduction in piezometric surface in the installed vibrating wire piezometers located in different aquifer units, indicating the Zambezi Border- and geological contact-faults were not barriers to groundwater flow. Not all the northwest-southeast trending dykes acted as barriers to groundwater flow, as there were discreet intervals with relatively high permeability present.
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Balia, Roberto, Enrico Gavaudò, Federica Ardau, and Giorgio Ghiglieri. "Geophysical approach to the environmental study of a coastal plain." GEOPHYSICS 68, no. 5 (September 2003): 1446–59. http://dx.doi.org/10.1190/1.1620618.
Повний текст джерелаАнотація:
In the study of coastal plains affected by soil and water salination, a knowledge of several geological aspects, such as structural features, depth to basement, stratigraphy of sedimentary cover, relationships between the phreatic aquifer and underlying aquifers, and the latter's structure, is basic to gaining an adequate understanding of both the causes and possible evolution of salination. In this framework, geophysical techniques can play a very important role. To improve the available geophysical information about the Muravera coastal plain, Sardinia, Italy, which is affected by severe soil and water salination, previously acquired electrical resistivity, reflection seismic and gravity data have been reprocessed, and a new seismic reflection survey has been conducted. Moreover, in order to give better support to the geological and hydrogeological interpretation of geophysical data, three boreholes were drilled. Reprocessed electrical data indicate the presence of a wide, electrically homogeneous low‐resistivity zone associated with salination phenomena. Reprocessed reflection data provide useful information on the near‐surface stratigraphy. The combined interpretation of resistivity and seismic results, supported by one calibration borehole, elucidates the relationships between the phreatic aquifer and the underlying confined aquifer. A new seismic reflection survey gives information on the depth to, and structure of, the Paleozoic basement, as well as on stratigraphic conditions of Pleistocene‐Holocene sediments. Finally, the combined interpretation of seismic, gravity, and well data results in a geological section containing most of the information considered essential, such as the interface between Holocene alluvium and Pleistocene alluvium, the thickness of the latter, and the structure and composition of the Paleozoic basement. The work as a whole shows how the combined application of geophysical techniques can in this specific situation provide wide‐ranging and high‐quality information that is essential for the realistic mathematical modeling of aquifer contamination, and can enable the rational planning of exploratory drillings.
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Almeida, João R. F. de, and Horst Frischkorn. "Salinization mechanisms of a small alluvial aquifer in the semiarid region of northeast Brazil." Revista Brasileira de Engenharia Agrícola e Ambiental 19, no. 7 (July 2015): 643–49. http://dx.doi.org/10.1590/1807-1929/agriambi.v19n7p643-649.
Повний текст джерелаАнотація:
The objective of this research was to identify and quantify the primary processes responsible for the increase in salinity observed in the alluvial aquifer during the dry season. Multivariate statistical analysis and inverse geochemical modeling were used to simulate possible salinization mechanisms in the alluvial aquifer. For this, by quantifying electrical conductivity and the concentrations of the ions Ca2+, Mg2+, Na+, K+, Cl-, HCO3- and SO42- in waters from the crystalline basement near the study area, water reservoirs near the alluvial aquifer and the studied alluvial aquifer, groups were formed and discriminant analysis was applied. Significance tests showed that direct evaporation has not only an influence on the alluvial aquifer, but also a mean volumetric contribution of 15.8% from waters of the crystalline basement, accompanied by processes of salt dissolution and precipitation, which would also justify the increase in salinity observed in the alluvial aquifer in the dry period.
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Ndikilar, Chifu E., B. Y. Idi, B. S. Terhemba, I. I. Idowu, and S. S. Abdullahi. "Applications of Aeromagnetic and Electrical Resistivity Data for Mapping Spatial Distribution of Groundwater Potentials of Dutse, Jigawa State, Nigeria." Modern Applied Science 13, no. 2 (January 3, 2019): 11. http://dx.doi.org/10.5539/mas.v13n2p11.
Повний текст джерелаАнотація:
Optimal mapping of groundwater resource is usually accomplished using integrated geophysical survey in which two or more techniques are applied. In this work, spectral analysis of aeromagnetic data was used to map the topography of the magnetic crystalline fresh basement underlying the water bearing aquifer of Dutse, Jigawa State Nigeria. Vertical electric sounding technique was used to detect the spatial distribution of the depths to the top of the aquifer within the same area. The overall goal of the work is to determine the groundwater potential of the area by mapping the spatial distribution of groundwater availability based on aquifer thickness and basement topography. The aquifer depth was found to be within the range of 5 to 15 m with a mean value of 10 m. The basement was found to be highly undulating having depths ranging from 6 to 69 m with a mean value of 24 m. The existence of isolated deep depressions within the basement which appears to be filled by water bearing sediments was thought to be favorable structures for groundwater accumulation. The spatial distribution of groundwater potential was therefore mapped in a reclassified image of three zones, high, moderate and low. The study therefore provides a vital tool for groundwater exploitation and management strategies.
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Dé Lasme, Omer Z., Avy S. Koffi, Oscar Z. Onetie, Lancine Diallo, and Xavier T. Ahondjo. "Characterization of the productivity of basement aquifers at Bagoué region (North of Côte d’Ivoire)." International Journal of Hydrology 7, no. 2 (May 16, 2023): 81–86. http://dx.doi.org/10.15406/ijh.2023.07.00343.
Повний текст джерелаАнотація:
This study aims to characterize the productivity of basement aquifers based on a database built by pumping test and drilling report from eighteen boreholes exploited in Bagoue region of Cote d’Ivoire. By using last version of a tool to assist in pumping test interpretation suggested by the French Mining and Geological Survey, Transmissivity parameter values of confined aquifers were determined through the well-known Theis method. In the same approach, critical yield value of borehole was determined at the equivalence point of linear and quadratic pressure drop from short-term pumping test data. Geostatistical analysis and kriging of transmissivity of aquifers were realized. Then, it was elaborated few predictive equations between hydrodynamic and hydraulic parameters based on their relationship level. Comparison of aquifers productivity and boreholes hydraulic capacity ended the methodology. Transmissivity ranged from 9.10-7 to 4.10-5 m2.h-1 while specific yield of boreholes reached between 0.34 and 23.07 m3.h-1. Yields from exploited boreholes varied between 0.5 m3.h-1 and 12 m3.h-1 with an average reaching 3.44 m3.h-1. Critical yield varied between 2.11 and 18.8 m3.h-1 with an average of 6.95 m3.h-1. According to geostatistical analysis of Transmissivity, its spatial spreading adjusted spherical model with a range reaching 0.13 meters. Findings highlighted 44 % of aquifer areas characterized by low value of transmissivity with great value of exploited outflow. That suggests a short-term availability of drinking water for living communities. In the same way, 11.11 % of boreholes were established into aquifer areas characterized by great transmissivity and low outflow values that suggests a better supply environment with long-term groundwater availability.
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Falowo, Olumuyiwa Olusola, Moses Philip Otuaga, Emmanuel Ajibola Lasore, Williams Kunle Olabisi, and Gbenga Olaifa. "Groundwater Prediction Analysis for Sustainable Development in Okeigbo, Southwestern Nigeria: A GIS supported AHP Approach." Indonesian Journal of Earth Sciences 3, no. 2 (September 25, 2023): A684. http://dx.doi.org/10.52562/injoes.2023.684.
Повний текст джерелаАнотація:
Multi-criteria decision analysis with GIS-supported Analytical Hierarchy Process (AHP) has been undertaken in Okeigbo, Southwestern Nigeria to predict the hydrogeologic significance of the aquifers and in relation to the geologic units; quartzite, quartz schist, and metadiorite. Six parameters of higher hydrogeologic importance were pairwise and weighted respectively: AQT-aquifer layer thickness (0.07), AQR-aquifer layer resistivity (0.16), OVT-overburden thickness (0.10), TR-transverse resistance (0.20), TMY-transmissivity (0.26), CoA-coefficient of anisotropy (0.22). Subsequently, the GWPIV ranged from metadiorite 1.08 (weathered/fracture aquifer)–quartz schist 3.55 (weathered aquifer) with an average of 2.35 indicating moderate groundwater potential. The low, moderate, and high zones constituted 25%, 55%, and 20% respectively of the study area. The high potential zone is prominent in the mid-central and north central parts. Conclusively, the quartz schist and quartzite areas showed better prolificacy than metadioritic environment. But in terms of protective capacity of the aquifers, the longitudinal unit conductance recorded weak regional average of 0.19396 mhos, with quartzite (0.33444 mhos) and quartz schist (0.15218 mhos); and metadiorite recorded 0.1208 mhos, hence metadiorite being the most vulnerable environment. The water table aquifer and the fracture basement are the major water bearing units in the area. The drainage basin falls within the low–moderate regional drainage basins, with moderate to high flow connectivity and low–moderate flow direction. Thus, there’s possibility of movement of water towards the northern part (discharged zone) with the southern area forming the watershed.
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Silva-Ávalos, Raúl Ulices, Hugo Enrique Júnez-Ferreira, Julián González-Trinidad, and Carlos Bautista-Capetillo. "Non-Linear 3D Satellite Gravity Inversion for Depth to the Basement Estimation in a Mexican Semi-Arid Agricultural Region." Applied Sciences 12, no. 14 (July 19, 2022): 7252. http://dx.doi.org/10.3390/app12147252.
Повний текст джерелаАнотація:
In Mexico, agriculture in semi-arid regions is highly dependent on groundwater resources, where most of the aquifers’ characterization is a pending task. In particular, the depth to the basement is unknown for most of the Mexican territory. Hence, the development and performance of new techniques for the basement relief estimation is imperative for further hydrogeological studies. In this paper, we present a depth to the basement estimation using non-linear gravimetric inversion employing satellite data. Gravity forward modeling was implemented using both gravitational attraction due to juxtapositioned blocks and gravimetric non-linear inversion using conjugate gradient least squares to minimize the objective function in terms of a depth model. All of this took place under the sparse system framework. We present a synthetic result using the SEG-Bishop depth model taken for calibration purposes. Then, we recollected gravity data from The Satellite Geodesy group from SCRIPPS for the depth to the basement estimation of an unconfined aquifer in the northern-central semi-arid region of Zacatecas, Mexico. Both synthetic and satellite data were recovered, consistent depth models for both cases were presented, and a comparison with conventional gravimetric linear inversion for density estimation was performed.
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M.S, Chaanda, and Alaminiokuma G.I. "HYDROGEOPHYSICAL INVESTIGATION FOR GROUNDWATER RESOURCE POTENTIAL IN MASAGAMU, MAGAMA AREA, FRACTURED BASEMENT COMPLEX, NORTH-CENTRAL NIGERIA." Malaysian Journal of Geosciences 4, no. 2 (May 15, 2020): 65–69. http://dx.doi.org/10.26480/mjg.02.2020.65.69.
Повний текст джерелаАнотація:
Vertical Electrical Sounding (VES) was conducted in Salbi farm in the fractured Basement Complex, North- Central Nigeria to determine the groundwater resource potential to serve for agricultural purposes. Four VES stations using Schlumberger electrode configuration with a maximum current electrode spread of 300m were employed for data acquisition. ZHODY software was employed in computing resistivities, depths and thicknesses of the various layers and curve types. Results indicate that the area is characterized by 3 distinct geoelectric layers inferred differently at the VES locations. One potential groundwater aquifer zone was delineated at VES 1, 2, and 4 within the fractured/weathered basement columns having depths ranging between 48.8 – 59.60m and resistivities ranging between 213 – 513 Ωm. These results suggest that boreholes for sustainable groundwater supply in Salbi farm should be sited either at VES 1, 2 or 4 location and screened at a depth ≥60.0m. Wells to develop this resource should be drilled to an effective depth of 40 to 60 m for optimum yields. It is recommended that pumping test be done in order to further determine the aquifer efficiency and productivity in the area. However, the aquifers at these locations have potentials for groundwater but may be vulnerable to contamination.
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Ervin, M. C., and J. R. Morgan. "Groundwater control around a large basement." Canadian Geotechnical Journal 38, no. 4 (August 1, 2001): 732–40. http://dx.doi.org/10.1139/t01-011.
Повний текст джерелаАнотація:
Melbourne's Crown Casino was constructed on a site bordering the Yarra River and underlain by problem soils of the Coode Island Silt Formation. The development needed to provide two levels of basement car park over the entire site. An innovative approach to groundwater control around the excavation was required to avoid depressurisation of adjoining soils, leading to settlements. Analysis showed a conventional bentonite cut-off wall would still allow depressurisation by lateral flow through the Coode Island Silt during the construction period. The high cost and construction difficulty of a very low permeability wall mitigated against it. An hydraulic wall was proposed in conjunction with a conventional cut-off wall. This comprised a curtain of wick drains surrounding the cut-off wall and charged with water. Control of seepage through an underlying aquifer by a cut-off wall was considered, but a more cost-effective method using recharge by wells was adopted when shown necessary. Monitoring of groundwater pressures around the site showed that the maximum change in water pressure was less than 1 m head, the design criterion. Part way through construction, recharge was initiated when monitoring of the deep aquifer showed pressure reduction attributed to vertical leakage through a basalt tongue.Key words: excavation, basements, groundwater, clays, settlement, monitoring.
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Yohanna, Andarawus, Nur Ahmad, Musa Nengak, Adamu Abubakar, and Mu’awiya B. Aminu. "Geoelectric investigation for aquifer characterization in Boi and Environs, Bauchi State, Northeast, Nigeria." Dutse Journal of Pure and Applied Sciences 8, no. 2a (June 24, 2022): 149–70. http://dx.doi.org/10.4314/dujopas.v8i2a.16.
Повний текст джерелаАнотація:
A total of thirty eight (38) Vertical Electrical resistivity Sounding (VES) were used to characterize aquifers in Boi and its environs, Bogoro Area of Bauchi State, Northeastern, Nigeria. The purpose of the study is to characterize the aquifer system in the area using Schlumberger configuration. Because there are multiple failed wells and boreholes in the vicinity, the research is justified. A total of 38 vertical electrical sounding (VES) were carried out, with a maximum electrode spacing of 100 m. The sounding curves acquired were three layer earth models, and the curve types were H, Q, A, and K respectively. The following lithologies were discovered in the area: topsoil with a resistivity of 81ῼm to 264.21ῼm and a thickness of 0.56m to 3.77m, laterite with a resistivity of 526.43ῼm to 999.71ῼm and a thickness of 1.93m to 3.47m, weathered/fracture basement with a resistivity of 10.62ῼm to 238ῼm and a thickness of 2m to infinite depth, and the fresh basement with a resistivity of 1000.33ῼm to 1821ῼm. The longitudinal conductance (S), transverse resistance (T), reflection coefficient (RC), and resistivity contrast (FC) were used to assess the area's groundwater potentials. The area's aquifer protection capacity found to be moderate, weak, and poor, while the groundwater potentials categorized as high, medium, low and very low. According to the results of the evaluated parameters, the area has a predominantly good to moderate groundwater potential. The numerous occurrences of failed/aborted boreholes in the area could be linked to a variety of factors, including poor data quality, lack of technical know-how, incorrect point selection, and poor drilled hole development, all of which are common in Basement Complex terrains. The VES 5 and 10 results showed a dramatic decline in resistivity, indicating that the water likely heavily polluted, particularly by anthropogenic chemicals, or that it was an ancient dumpsite.
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Olajide, O. R., I. A. Adeyemo, and S. O. Olaogun. "Geo-spatial Classification of Vulnerability Zones using Lithological, Elevation and Geoelectric Parameters in a Typical Basement Complex Environment." Nigerian Journal of Basic and Applied Sciences 29, no. 1 (February 8, 2022): 13–22. http://dx.doi.org/10.4314/njbas.v29i1.2.
Повний текст джерелаАнотація:
Lithology, elevation and four (4) geoelectric parameters were utilized in assessing the groundwater vulnerability at northwestern part of Akure, southwestern Nigeria. Vertical electrical sounding (VES) technique of electrical resistivity method was adopted for this work. A total of 224 VES data was acquired and interpreted both qualitatively and quantitatively. Three to five geo-electric layers were delineated across the area which corresponds to four geologic layers. The resistivity of the layers varies respectively from 6.9 - 550 Ohm-m, 60 - 2500 Ohm-m, 20 - 650 Ohm-m and 220 - 7900 Ohm-m in the topsoil, weathered layer, partially weathered basement/partially fractured basement and presumed fresh basement. Likewise, the layer thicknesses also vary respectively from 0.4 - 4.0 m, 0.7 - 19.0 m and 4.0 -60 m in the topsoil, weathered layer and partially weathered basement/partially fractured basement. The results were presented as topsoil (resistivity and thickness) and weathered layer (resistivity and thickness) maps. The six parameters consisting of lithology, elevation, topsoil (resistivity and thickness) and weathered layer (resistivity and thickness) were synthesized using an additive model in order to generate the aquifer vulnerability model map. The aquifer vulnerability model map shows that the area is of very low to moderate vulnerability with 5% of the area having very low vulnerability, 30% low vulnerability and 65% moderate vulnerability. This implies that the groundwater resources in the area are moderately safe.
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Almeida, Ghislaine M. de, and Gerson Cardoso da Silva Junior. "Fatores hidrogeológicos no estudo da intrusão salina em aqüíferos costeiros da região litorânea do município de Maricá - RJ." Anuário do Instituto de Geociências 30, no. 2 (December 1, 2007): 104–17. http://dx.doi.org/10.11137/2007_2_104-117.
Повний текст джерелаАнотація:
The oceanic area of Maricá, in the east coast of the Rio de Janeiro State, relies on groundwater as its main source of fresh water supply along with the use of water tank trucks. With the increasing demand of water resources, water supply and contamination problems are foreseen, and sea water intrusion phenomenon is also expected in these aquifers. The groundwater resource of the target area has been submitted to quality degradation due to the advance of the saline wedge, the excess of pumping without control and also the pollution of organic origin. Considering this situation, the study aims to contribute to a better knowledge of the hydrogeological characteristics in order to assist the aquifer management of the coastal area under study. The area comprises a granular aquifer and local geology consists basically of marine and fluvio-marine Quaternary sandbar deposits, overlying a crystalline basement of variable depth. The study included the evaluation of previously existing hydrological data in the area, rainfall data, and a field survey in 41 wells, with measurements of hydrodynamic and physical-chemical parameters (temperature, electric conductivity, hydraulic head). Furthermore, an automatic instrumentation was installed to evaluate the response of the aquifer to recharge. Results indicate that aquifer salinity levels tend to rise in the SE portion, and also, apparently, there has been an increase in aquifer salinization in recent years, demanding urgent management actions. The automatic instrumentation shows that Maricá coastal aquifer gives a rapid response to seasonal factors and climate, showing some vulnerability, but also rapid recharge and dilution capacity.
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Aina, J. O., O. O. Adeleke, V. Makinde, H. A. Egunjobi, and P. E. Biere. "Assessment of Hydrogeological Potential and Aquifer Protective Capacity of Odeda, Southwestern Nigeria." Materials and Geoenvironment 66, no. 3 (April 24, 2020): 199–209. http://dx.doi.org/10.2478/rmzmag-2019-0015.
Повний текст джерелаАнотація:
AbstractHydrogeological assessment of groundwater resources was carried out with a view to evaluate the potential of the aquifers to provide portable water supply and access the distribution of electrical parameters of hydrogeologic units in some areas in Odeda, Ogun State, Nigeria. A geophysical survey using vertical electrical sounding (VES) with the Schlumberger electrode array, with half-current electrode spacing (AB/2) varying from 1 to 132 m was carried out at 30 different stations in the study area. The VES data were interpreted qualitatively and quantitatively. Three-to-five sub-surface layers consisting of topsoil, weathered layer consisting of clay, sandy clay, clayey sand and sand layers, and fractured/fresh basement were delineated. Layer resistivities and thicknesses obtained on the curves within the study area showed one main aquifer type, which is the fractured basement. The longitudinal unit conductance (ranging from 0.049720 to 1.4520000 mhos) of the study area aided the protective capacity to be rated into good, moderate and weak. About 33% of the study area falls within the weak protective capacity, 57% falls within the moderate protective capacity and 10% falls within the good protective capacity.
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Jørgensen, N. O., and J. Heinemeier. "Origin of brackish groundwater in a sandstone aquifer on Bornholm, Denmark." Hydrology Research 39, no. 3 (June 1, 2008): 209–22. http://dx.doi.org/10.2166/nh.2008.043.
Повний текст джерелаАнотація:
A multi-isotope approach in combination with hydrochemical data and borehole logging is applied to identify the source of brackish groundwater in a borehole in the well field of Neksø Municipal Waterworks in Bornholm, Denmark. The aquifer lithology consists of fractured Lower Cambrian sandstones resting on Proterozoic crystalline basement. The water body in the studied borehole is significantly stratified with respect to the hydrochemical and isotopic signatures and reveal a Na–Ca–Cl–HCO3 water type and TDS values >1,000 mg/L below a halocline at 40–55 m below measurement point (bmp). The occurrence of brackish groundwater is remarkable for this aquifer, which otherwise yields potable groundwater of good quality. The stable isotope (18O and 2H) compositions indicate a meteoric origin of the brackish groundwater, which rules out seawater intrusion into the aquifer. 14C activities show apparent 14C ages of the brackish groundwater in the range 2200–4300 yr (BP), whereas the freshwater samples above the halocline indicate modern age. Hydrochemical (Cl/Br and Sr) and isotopic studies (18O, 2H and 87Sr/86Sr) of the brackish groundwater point to a well-mixed and homogeneous water body reflecting long water–rock interaction and suggest a contribution of palaeowater from the fractured crystalline basement which has intruded into the Lower Cambrian sandstone aquifer.
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Srivastava, Ajay, Nitin Kumar Tripathi, and K. V. G. K. Gokhale. "Basement topography and aquifer geometry around Ken Graben, India." International Journal of Remote Sensing 20, no. 11 (January 1999): 2295–305. http://dx.doi.org/10.1080/014311699212263.
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Van Lam, Van Hoan, and Duc Nhan. "Investigation into Groundwater Resources in Southern Part of the Red River’s Delta Plain, Vietnam by the Use of Isotopic Techniques." Water 11, no. 10 (October 12, 2019): 2120. http://dx.doi.org/10.3390/w11102120.
Повний текст джерелаАнотація:
Groundwater in the Red River’s delta plain, North Vietnam, was found in Holocene, Pleistocene, Neogene and Triassic aquifers in fresh, brackish and saline types with a total dissolved solids (TDS) content ranging from less than 1 g L−1 to higher than 3 g L−1. Saline water exists inHolocene aquifer, but fresh and brackish water exist in Pleistocene, Neogene and Triassic aquifers. This study aims at the investigation into genesis and processes controlling quality of water resources in the region. For this isotopic, combined with geochemical techniques were applied. The techniques include: (i) measurement of water’s isotopic compositions (δ2H, δ18O) in water; (ii) determination of water’s age by the 3H- and 14C-dating method, and (iii) chemical analyses for main cations and anions in water. Results obtained revealed that saline water in Holocene aquifer was affected by seawater intrusion, fresh water in deeper aquifers originated from meteoric water but with old ages, up to 10,000–14,000 yr. The recharge area of fresh water is from the northwest highland at an altitude of 140–160m above sea level. The recharge water flows northwesterly towards southeasterly to the seacoast at a rate of 2.5m y−1. Chemistry of water resources in the study region is controlled by ferric, sulfate and nitrate reduction with organic matters as well as dissolution of inorganic carbonate minerals present in the sediment deposits. Results of isotopic signatures in water from Neogene, Triassic and Pleistocene aquifers suggested the three aquifers are connected to each other due to the existence of faults and fissures in Mesozoic basement across the delta region in combination with high rate of groundwater mining. Moreover, the high rate of freshwater abstraction from Pleistocene aquifer currently causes sea water to flow backwards to production well field located in the center of the region.
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Durand, Véronique, Benoît Deffontaines, Véronique Leonardi, Roger Guerin, Robert Wyns, Ghislain de Marsily, and Jean-Luc Bonjour. "A multidisciplinary approach to determine the structural geometry of hard-rock aquifers. Application to the Plancoet migmatitic aquifer (NE Brittany, W France)." Bulletin de la Société Géologique de France 177, no. 5 (September 1, 2006): 227–36. http://dx.doi.org/10.2113/gssgfbull.177.5.227.
Повний текст джерелаАнотація:
Abstract A new multidisciplinary methodology is developed to determine the structural geometry of hard-rock aquifers. The Plancoët migmatitic basement, chosen as an example for the use of this methodology, is studied both at a regional (300 km2) and a local (4 km2) scale. The regional mapping, based on field mapping of the tectonic structures and the weathered layers, on geostatistics and on aerial photographs and Digital Elevation Model (DEM) analyses, demonstrates the influence of the tectonic structures on the weathering processes. Some geo-electric investigations, added to the first mapping at the local scale, lead to the building of a local geometrical model of the aquifer.
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Ram Babu, H. V., N. Kameswara Rao, and V. Vijay Kumar. "Bedrock topography from magnetic anomalie—An aid for groundwater exploration in hard‐rock terrains." GEOPHYSICS 56, no. 7 (July 1991): 1051–54. http://dx.doi.org/10.1190/1.1443113.
Повний текст джерелаАнотація:
The role of the magnetic method in groundwater exploration is to locate structures such as dikes, faults, fractures, etc., that control the accumulation and movement of groundwater. In hard‐rock terrains, the thickness of the weathered layer is an important parameter that determines the quantity of groundwater accumulated in the unconfined aquifer above the basement. The basement rock, in the process of weathering, loses its magnetic properties and becomes much less magnetic. Therefore, the magnetic response is mostly due to the unweathered hard basement rock, and the depths of magnetic sources obtained from the analysis give us the top of the basement. Information about the thickness of the weathered layer would help in assessing the groundwater potential of the region.
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El-Meselhy, A., and G. M. Mitrofanov. "STUDY OF AQUIFER LAYERS: AN EXAMPLE OF EL-OWEINAT REGION, EGYPT." Geology and mineral resources of Siberia, no. 4 (December 2022): 70–84. http://dx.doi.org/10.20403/2078-0575-2022-4-70-84.
Повний текст джерелаАнотація:
The analysis of the geological structure of aquifer layers made it possible to solve two important tasks: (1) determination of the aquifer system and groundwater flow, (2) assessment of the well efficiency of existing productive wells. The resulting solution was based on three-dimensional modeling using borehole geophysical data and the involvement of comprehensive information on the development of water resources. The result was new knowledge about the studied aquifer system in its geophysical, geological and field context. It consists in determining: the static water depth and the direction of the main flow, the structure of the aquifer with the distribution of aquifer layers and aquitard layers, basement rocks, as well as the well efficiency and the aquifer loss coefficients. These measures make it possible to increase the well efficiency and managing the process of pumping water from existing wells, as well as to optimize the drilling of new wells in the area under consideration.
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Shaibu, I., Udensi, E. E., Chinwuko, A. I., and Ovwasa, M. O. "Geoelectric Investigation of the Subsurface Structures in Part of Gidan Kwano Campus of the Federal University of Technology, Minna, Nigeria." International Journal of Science for Global Sustainability 4, no. 2 (December 28, 2017): 10. http://dx.doi.org/10.57233/ijsgs.v4i2.178.
Повний текст джерелаАнотація:
Geoelectric investigations of the subsurface structures of parts of the Gidan Kwano campus Federal University of Technology (F.U.T) Minna, Nigeria were carried out using vertical electrical soundings technique. The area lies within the Pre-Cambian Basement Complex of Northern Nigeria. This study was carried out with the aim of determining subsurface structures of the area for groundwater potentials and to possibly locate those areas that could be useful for civil engineering work at a very low risk. Thirty-six vertical electrical soundings along six profiles (A-F) were carried out during the geophysical survey. The survey was carried out on grid 500m x500m. The data obtained were interpreted using computer based program named Zohdy. The result of the interpreted vertical electrical soundings (VES) curves reveals three distinct geo-electric curves types were delineated: K, H and HK-curves with H-type having the most prolific aquifer. The result also shows 3 geo-electric layers which were confirm by borehole lithology. The aquifers in the study area are likely to be found in the fractured basement layers of eastern and southeastern parts of the study area. The civil engineering work can be sited in the northern and southwestern parts of the study area which are the region of shallow basement.
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Agada, Livinus Emeka, and M. S. Yakubu. "EVALUATION OF AQUIFER PROTECTIVE CAPACITY USING ELECTRICAL RESISTIVITY METHOD IN LAMBATA, KWALI AREA COUNCIL, ABUJA." FUDMA JOURNAL OF SCIENCES 6, no. 3 (July 2, 2022): 191–99. http://dx.doi.org/10.33003/fjs-2022-0603-993.
Повний текст джерелаАнотація:
This study evaluated the aquifer protective capacity of Lambata in Kwali area council of Abuja, using electrical resistivity method. The obtained data were interpreted manually by partial curve matching and the obtained results were iterated using WINREIST software. The first layer is the topsoil whose resistivity range from 127.7 to 562.4 Ωm and its thickness range from 0.7 to 1.6 m. The second layer is laterite and its resistivity range from 302.3 to 937.6 Ωm, the thickness of the second layer range from 3.7 to 13.3 m. The third layer is a clay formation whose resistivity range from 46.7 to 88.8 Ωm and its thickness range from 6.6 to 27.9 m. The fourth layer is a weather/ fractured basement, this layer is the aquifer and it is confined by the overlying clay formation. Its resistivity range from 59.0 to 870.2 Ωm, while its thickness range from 6.0 to 28.5 m. The fifth layer is the fresh basement whose resistivity range from 1038.5 to 4992.5 Ωm. The total longitudinal conductance values of the overburden in the study area range from 0.00143 to 0.410334 mΩ-1. The average aquifer thickness in the study area is 16.60 m. The aquifer protective capacity is about 93.3% moderate and 6.7% weak. The aquifer protective capacity of the study area is fairly good but not sufficient to protect the groundwater in the area from pollution. We therefore strongly suggest that there should be proper environmental and waste monitoring management in the study area to safeguard the groundwater
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Varga, Andrea, Gábor Bozsó, István Garaguly, Béla Raucsik, Attila Bencsik, and Balázs Kóbor. "Cements, Waters, and Scales: An Integrated Study of the Szeged Geothermal Systems (SE Hungary) to Characterize Natural Environmental Conditions of the Thermal Aquifer." Geofluids 2019 (April 24, 2019): 1–21. http://dx.doi.org/10.1155/2019/4863814.
Повний текст джерелаАнотація:
The study area, Pannonian Basin (Central Europe), is characterized by high heat flow and presence of low-enthalpy geothermal waters. In the Szeged Geothermal Systems (Hungary), having Miocene to Pliocene sandstone aquifers with dominantly Na–HCO3-type thermal water, unwanted carbonate scaling was observed. An integrated approach consisting of host rock and scale mineralogical and petrographic analyses as well as water chemistry led to a better understanding of the characteristic natural (geogenic) environmental conditions of the geothermal aquifers and to highlight their technical importance. Analyses of the reservoir sandstones showed that they are mineralogically immature mixed carbonate-siliciclastic rocks with significant macroporosity. Detrital carbonate grains such as dolomite and limestone fragments appear as important framework components (up to ~20–25%). During water–rock interactions, they could serve as a potential source of the calcium and bicarbonate ions, contributing to the elevated scaling potential. Therefore, this sandstone aquifer cannot be considered as a conventional siliciclastic reservoir. In mudrocks, a significant amount of organic matter also occurs, triggering CO2producing reactions. Correspondingly, framboidal pyrite and ferroan calcite are the main cement minerals in all of the studied sandstone samples which can suggest that calcite saturation state of the thermal fluid is close to equilibrium in oxygen-depleted pore water. Analysis of the dominant carbonate crystals in the scale can suggest that growth of the feather dendrites of low-Mg calcite was probably driven by rapid CO2degassing of CO2-rich thermal water under far-from-equilibrium conditions. Based on hydrogeochemical data and related indices for scaling and corrosion ability, the produced bicarbonate-rich (up to 3180 mg/l) thermal water has a significant potential for carbonate scaling which supports the aforementioned statement. Taking into consideration our present knowledge of geological setting of the studied geothermal systems, temporal changes in chemical composition and temperature of the thermal water during the heating period can indicate upwelling fluids from a deep aquifer. Regarding the pre-Neogene basement, hydrologic contact with a Triassic carbonate aquifer might be reflected in the observed chemical features such as decreased total dissolved solids and increased bicarbonate content with high scale-forming ability. The proposed upflow of basin-derived water could be channeled by Neogene to Quaternary fault zones, including compaction effects creating fault systems above the elevated basement high. The results may help to understand the cause of the high carbonate scale precipitation rates in geothermal systems tapping sandstone aquifers.
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Hamdy Eid, Mohamed, Péter Szűcs, and Attila Kovács. "Problems Threatening Sustainability in Siwa Oasis and Recommendations for Understanding the Sources of Water Quality Deterioration." Geosciences and Engineering 10, no. 15 (2022): 138–53. http://dx.doi.org/10.33030/geosciences.2022.15.138.
Повний текст джерелаАнотація:
Siwa Oasis has been chosen as the location for the current investigations. Siwa Oasis is an isolated closed depression located in Egypt’s Western desert. It is surrounded by the Mediterranean Sea to the north (about 330 km), to the west by the Libya-Egypt border (70 km) and Cairo to the east (560 km). There are three major activities in Siwa Oasis: that are represented by agriculture (palm tree, olive, fruits and vegetables), industry, (e.g. mineral water bottling and olive oil extraction), and tourism (medical treatment, safaris). The climate of the Western Desert, particularly in Siwa, is generally torrid and arid. The Siwa depression is occupied by Quaternary deposits (aeolian deposits and lakes), Middle Miocene, Upper Cretaceous (sandstone), and Precambrian (basement complex). The groundwater system in Siwa Oasis hastwo main productive aquifers: a Miocene aquifer (fractured limestone) and a Lower Cretaceous aquifer (Nubian Sandstone). Besides, the Quaternary (clay and sand) uppermost layer is water-bearing because of waterlogging. Siwa Oasis is suffering from waterlogging, increasing soil salinity, and deterioration of water quality in the aquifers. This review includes the problems in Siwa Oasis and recommendations for understanding hydrogeological situations and sources of water quality deterioration to avoid waterlogging and soil salinization through integration of flow modeling, geochemistry and isotopic tracers.
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Blanco-Coronas, Angela M., Maria L. Calvache, Manuel López-Chicano, Crisanto Martín-Montañés, Jorge Jiménez-Sánchez, and Carlos Duque. "Salinity and Temperature Variations near the Freshwater-Saltwater Interface in Coastal Aquifers Induced by Ocean Tides and Changes in Recharge." Water 14, no. 18 (September 9, 2022): 2807. http://dx.doi.org/10.3390/w14182807.
Повний текст джерелаАнотація:
The temperature distribution of shallow sectors of coastal aquifers are highly influenced by the atmospheric temperature and recharge. However, geothermal heat or vertical fluxes due to the presence of the saline wedge have more influence at deeper locations. In this study, using numerical models that account for variable density, periodic oscillations of temperature have been detected, and their origin has been attributed to the influence exerted by recharge and tides. The combined analysis of field data and numerical models showed that the alternation of dry and wet periods modifies heat distribution in deep zones (>100 m) of the aquifer. Oscillations with diurnal and semidiurnal frequencies have been detected for groundwater temperature, but they show differences in terms of amplitudes and delay with electrical conductivity (EC). The main driver of the temperature oscillations is the forward and backward displacement of the freshwater–saltwater interface, and the associated thermal plume generated by the upward flow from the aquifer basement. These oscillations are amplified at the interfaces between layers with different hydraulic conductivity, where thermal contours are affected by refraction.
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Kafando, Moussa Bruno, Mahamadou Koïta, Cheick Oumar Zouré, Roland Yonaba, and Dial Niang. "Quantification of Soil Deep Drainage and Aquifer Recharge Dynamics according to Land Use and Land Cover in the Basement Zone of Burkina Faso in West Africa." Sustainability 14, no. 22 (November 8, 2022): 14687. http://dx.doi.org/10.3390/su142214687.
Повний текст джерелаАнотація:
Groundwater is a vital water supply for local populations and ecosystems globally. With the continuous population growth, the anthropic pressure on groundwater is ever increasing, thus reducing the amount of available water resource. Yet, estimating the impact of anthropogenic activities on aquifer recharge is still a significant challenge for research, especially in basement aquifers. This study aims to improve the actual knowledge of deep drainage and deep aquifer recharge pathways and dynamics in the basement as affected by land use/land cover (LULC). The methodology used in this study accounted for hydraulic processes in soil layers within both unsaturated and saturated zones in an integrated approach. An experimental setup consisting of three (3) experimental plots, respectively under natural vegetation (NV), cropped millet (CM) and cropped groundnut (CG) on which deep drainage was monitored during the years 2020 and 2021. The results show significant differences between the LULC types after two years of implementation. Deep drainage is improved under CM and CG plots located in the central valley, as compared to the NV plot located in the ridge zone. Deep drainage is estimated at 8%, 24% and 25% of the annual rainfall, respectively for NV, CM and CG. The ratio between the recharge value obtained by the water table fluctuation (WTF) method and the deep drainage tends to 1 for the CM and CG plots, highlighting a rapid water transfer between unsaturated and saturated zones. The central valley, which seems to be a preferential recharge pathway, provides promising insights under specific conditions for the implementation of artificial recharge infrastructures.
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Olawuyi, Ayodele Kehinde. "Hydrogeophysical investigation for the aquifers in part of Ilorin, Central Nigeria: Implication on groundwater prospect." Tanzania Journal of Science 47, no. 2 (May 11, 2021): 520–34. http://dx.doi.org/10.4314/tjs.v47i2.10.
Повний текст джерелаАнотація:
Hydrogeophysical study involving the use of Vertical Electrical Sounding (VES) was carried out in part of the basement complex rocks of Ilorin, central Nigeria, with the aim of determining its geoelectric parameters and groundwater potential. A total of thirty (30) VES were carried out using Schlumberger electrode configuration, with half electrode separation (AB/2) varying from 1m to 100m. Information on the subsurface lithologies, overburden thickness and aquiferous layers were obtained from the different VES locations in the study area. From the quantitative interpretations of the data collected, using the method of curve matching with the Orellana-Mooney master curves and 1-D forward modeling with WinResist 1.0 version software, three to five lithologic units were identified in the study. These include: the topsoil, sandy/lateritic clay/laterite, the weathered basement, the fractured basement and the fresh bedrock which are predominantly of the ‘KH’ curve type (30%), followed by ‘H’ type (26.7%), other type curves include ‘QH’ (16.7%), ‘HKH’, ‘HA’ and ‘A’ (6.7% each) and KQ and KQH (3.3% each). The weathered layer and the fractured basement constitute the main aquifer units. The aquifers are of generally low resistivity values (mostly below 100 Ω-m). The depths to dry bedrock at the chosen VES locations vary from 2.7 to 62.7 m with a mean value of 13.02 m in the study area. The geoelectrical interpretations of data obtained in these areas have permitted the delineation of the study area into low and moderate groundwater potential zones. This study is expected to assist in future planning for groundwater resources.
Keywords: Hydrogeophysical, Basement Complex, Groundwater, Electrical Soundings, Weathered, Fractured
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Akinrinade, Opeyemi J., and Rasheed B. Adesina. "Hydrogeophysical investigation of groundwater potential and aquifer vulnerability prediction in basement complex terrain – A case study from Akure, Southwestern Nigeria." Materials and Geoenvironment 63, no. 1 (June 1, 2016): 55–66. http://dx.doi.org/10.1515/rmzmag-2016-0005.
Повний текст джерелаАнотація:
AbstractThis study provides a model for the prediction of groundwater potential and vulnerability of basement aquifers in parts of Akure, Southwestern Nigeria. Hydrogeophysical surveys involving very-low-frequency electromagnetic (VLF-EM) profiling and electrical resistivity (ER) sounding, as well as evaluation of hydraulic gradient using three-point method, were carried out. Ten VLF-EM reconnaissance survey traverses, with lengths ranging from 55 m to 75 m, at 10 m station separation, and 12 vertical electrical sounding (VES) stations were occupied. Two-dimensional map of the filtered real component reveals areas of high conductivity, indicative of linear features that can serve as a reservoir or conduit for fluid flow. Interpretation of the VES results delineates three to four geoelectric units. Two aquifer zones were identified, with resistivity values in the ranges of 20 Ωm to 310 Ωm and 100 Ωm to 3,000 Ω m, respectively. Transverse resistance, longitudinal conductance, coefficient of anisotropy and hydraulic gradient have values ranging from 318.2 Ωm2 to 1,041.8 Ωm2, 0.11 mhos to 0.39 mhos, 1.04 to 1.74 and 0.017 to 0.05, respectively. The results of this study identified two prospective borehole locations and the optimum position to site the proposed septic system, based on the aquifer’s protective capacity and groundwater flow properties.
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ADAMU, JOHN, Olarenwaju Ade Olanite, and Adamu Yunusa. "GROUNDWATER POTENTIAL INVESTIGATION USING 1-D ELECTRICAL RESISTIVITY TECHNIQUE AT NIGER STATE POLYTECHNIC ZUNGERU, ZUNGERU MAIN CAMPUS, NIGER STATE, NIGERIA." FUDMA JOURNAL OF SCIENCES 5, no. 4 (February 21, 2022): 392–99. http://dx.doi.org/10.33003/fjs-2021-0504-825.
Повний текст джерелаАнотація:
Electrical resistivity method employing vertical electrical sounding was carried out with aim to investigate groundwater potential at Niger State Polytechnic, Zungeru, Niger State. Ten points were selected at different locations within the campus for vertical electrical sounding (VES), using Schlumberger protocol. Maximum current electrodes separation (AB) of 120m was used. The investigation was carried out using Terrameter PE 02 SAS 300 system. The survey was able to investigate groundwater potential of the area. The IPI2win software was used for data analysis. The geologic section derived from geoelectric parameters revealed three subsurface layers. The first layer is interpreted as topsoil, the second layer is inferred to be weathered rock, while the third layer probably could be fresh basement rock. The thickness of the superficial cover is averagely 2.49m, and the depth to the basement is between 5.2m to 22.9m, the aquifer thickness ranges between 1.67 to 21.1m. The laterite in the second layer shown in some locations is of great importance as it reduces surface run off and aids infiltration into the underlying aquifer. The thickness of the aquifer component in the north-southern half of the study area is large enough to harbour substantial quantity of water. Areas around ZUN 01 and ZUN 05 could be potential areas for groundwater exploration. In this research, the depth to bedrock and aquifer thickness were determined, lithological formations within the overburden were delineated and approximate depths
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Adamu, S., A. K. Yusuf, A. G. Kodomi, and I. B. Wulo. "A Reconnainsances Study to Delianate Conductive Groundwater Zone Using Resistivity Sounding in Some Part of Kwara State North-Central, Nigeria." Journal of Geography and Geology 12, no. 2 (August 31, 2020): 57. http://dx.doi.org/10.5539/jgg.v12n2p57.
Повний текст джерелаАнотація:
From the results, three to four electrostratigraphic layers with resistivity value ranging from 44 to 997 ohm/m and thickness ranging from 0.5 to 39.7 m were observed in the study area. The top loose rocks, the weathered conductive zone, the fractured basement rock and the fresh basement rock of older granite suite were encountered respectively. From this research, it can be deduce that, the thicker top soil and deeper weathered basement rock at the depth of 30 to 45 meters within this area produce a productive site for sitting future borehole. Insufficient groundwater supply in some places leading to scarcity is noticed in VES 10, VES 12 and VES 13. H, I, and A curve types are generally the most common in the area and are typical of basement complex area. Geographical Positioning System tool (model: GPSmap 76CSx), was used to locate the VES points. Fifteen VES points with electrode spacing [AB/2] of 100 meters separation around Ndanaku and environs were undertaken using Schlumberger configuration. IPI 2 Win [1990-2003] Geosoft resistivity sounding software was used to model the field curves from the measured data on the field. Groundwater in the area is regarded as poor due to localized nature of the aquifer and the study aimed at addressing this scarcity of water within the area by studying the conductive zone and knows the aquifer types through resistivity sounding techniques for future drilling.
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O.O., Olukayode, Bayewu O.O., Adebisi N.O., Mosuro G.O., Ariyo S.O., and Orimogunje O.B. "Multi-Criteria Analysis Method for Aquifer Vulnerability Investigation Using Godt Method at Idi-Ayunre, Ibadan, Southwestern Nigeria." African Journal of Environment and Natural Science Research 6, no. 2 (August 1, 2023): 97–112. http://dx.doi.org/10.52589/ajensr-7df7dj7o.
Повний текст джерелаАнотація:
Geophysical investigation involving Vertical Electrical Sounding (VES) Schlumberger array was carried out across Idi-Ayunre, Ibadan, a typical basement complex area having a rock composition of migmatite-gneiss, quartzite, and biotite-hornblende. A total of forty (40) vertical electrical sounding data were acquired with maximum current electrode separation of 100m using resistivity meter and its accessories. The aim of the study was to evaluate the aquifer vulnerability of the study area to contamination. The VES results were both qualitatively and quantitatively interpreted using partial curve matching and were further subjected to computer iteration using WINRESIST. The longitudinal conductance, thickness of layer overlying aquifer and hydraulic conductivity were generated and synthesized to produce the vulnerability map. A GODT multi-criteria model which is an acronym of Groundwater occurrence, Overburden thickness, Depth and Topography developed from the hydrogeologic parameters were evaluated alongside the longitudinal conductance values to determine the aquifer vulnerability of the area and to classify the study area accordingly. The curve type obtained are H and HA. The interpretation revealed three to four geoelectric layers: the topsoil (18.9-178.9Ωm), clayey (9.0-70.6Ωm), fractured basement (31.9-43.1Ωm) and fresh basement (1131-2916Ωm). The longitudinal unit conductance ranges from 0.032-0.93mhos. And from the GODT model derivations, the study area shows 92.5% of high vulnerability rating, 2.5% of low-moderate and 5% of moderate rating; areas with high rating are prone to contamination than areas with low-moderate and moderate rating. Hence, zones of high vulnerability may be not be encouraged for groundwater exploitation and, if need be, constant water quality assessment should be carried out before consumption.
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Ahmed, Mohamed, Sultan Araffa, Tarek Hamed, Taha Rabeh, Ahmed Helaly, and Karam Farag. "Groundwater Inspection and Aquifer Assessment Using Magnetotellurics and Magnetic Data at the Reclamation Area Around New Sphinx City, Egypt." Iraqi Geological Journal 57, no. 1C (March 31, 2024): 214–42. http://dx.doi.org/10.46717/igj.57.1c.15ms-2024-3-27.
Повний текст джерелаАнотація:
Nine Magnetotelluric stations and 198 Land-Magnetic points were conducted within reclamation regions at the western and southwestern areas of the New Sphinx City, Egypt. The main target is to explore the deep groundwater aquifer (Nubian Aquifer), and its reserves. This was interpreted with integrated data available from thirteen water wells within the studied area. Their depths range from 160 to 773 m. We noticed that the wells don’t reach the Nubian Aquifer and the groundwater in the area comes from the Jurassic-Lower Cretaceous, the Upper Cretaceous-Eocene Limestone, and the Oligo-Miocene aquifers, which contain brackish/saline water. The groundwater table ranges between 128-170 m from the topographic-controlled ground surface. Structurally, the area is dissected by two major thrust faults trending in the NE-SW direction, while there is one major normal fault trending in the NW-SE direction. The results showed that the basement relief ranges between -2250 to -4650 m below mean sea level. The Nubian Aquifer extends through the central region within the area according to the results of Nine Magnetotelluric data. It is bounded by the two inverted faults within the Kattaniya inverted basin which is gradually thinning in the southward direction to disappear completely at the Gindi basin. It is partitioned into two units; the upper one was found at an average depth range between -1760 to -2245 m with an average thickness of about 485 m, while the lower unit depth ranges between -2800 to -3825 m with an average thickness of about 1025 m.
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Shaibu, Isah, M. O. Ovwasa, and A. Misbahu. "EVALUATION OF THE SUBSURFACE STRUCTURES IN PART OF FEDERAL UNIVERSITY OF GUSAU CAMPUS , ZAMFARA STATE, NIGERIA." FUDMA JOURNAL OF SCIENCES 6, no. 1 (April 11, 2022): 338–50. http://dx.doi.org/10.33003/fjs-2022-0601-906.
Повний текст джерелаАнотація:
Geo-electric evaluations of the subsurface structures of federal University Gusau Campus, Zamfara State, Nigeria were carried out using vertical electrical soundings technique (VES). The area lies within the Pre-Cambian Basement Complex of Northern Nigeria. Thirty-six (36) vertical electrical soundings (VES) along six profiles (A-F) were carried out during the survey. The surveys were carried out on grid 500m by 500m. The data obtained were interpreted using computer based program named Zohdy. The result of the interpreted curves reveals three distinct geo-electric curves types were delineated: K, H and HK-curves with H-type having the most prolific aquifer. The result also shows 3 geo-electric layers which were confirm by some borehole lithology. The aquifers in the study area are likely to be found in the fractured basement layers of western and southeastern parts of the study area. The civil engineering work can be sited mostly in the northern and southwestern parts of the study area which are the region of shallow basement within t=he study areas. Further boreholes in the area should reached an effective depth of 75m to 90m and the borehole be supervised by a certified hydrogeologist for optimum groundwater yields. Pumping test should be carried out in order to ascertain the size and type of submersible pump to install.
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Olawuyi, A. K., and M. A. Bawallah. "Integrated geophysical methods and techniques for studying the perennial springs in Ikanje- Share, Kwara State, Nigeria." Nigerian Journal of Basic and Applied Sciences 30, no. 1 (August 25, 2022): 68–76. http://dx.doi.org/10.4314/njbas.v30i1.10.
Повний текст джерелаАнотація:
An integrated magnetic, self-potential (S.P.) and electrical resistivity survey involving magnetic profiling and 1D Vertical Electrical Sounding (VES) electrical imaging techniques were carried out in the transition environment between the Nupe Basin and Southwestern Nigeria Basement Complex at Ikanje-Share in Kwara State, Nigeria. The Ikanje-Share perennial springs started gaining a lot of attention after many travelers and tertiary institutions in Nigeria made it a good choice for their fieldwork exercise. The surveys were done in order to delineate the subsurface layers, determine the geoelectrical characteristics and identify geological structures (e.g., faults and fractures) that are responsible for the perennial spring formation. The magnetic profiling was used as reconnaissance technique to identify lineament features that are favourable to groundwater accumulation and transmission. Some magnetic lineaments were qualitatively inferred from some profiles in the study area. The fault locations coincide with inflection points in S.P. curves and occur as horizontal and consistent planes of discontinuities at depths of approximately 1.25, 4.25, 8.75, 13.15 and 21.25 m, respectively. The VES interpretation results indicated four to five major geologic units, which include: the topsoil/clay/lateritic layer, the lateritic layer, the weathered basement, the weathered/fractured basement and the fresh bedrock. The weathered and fractured basements constitute the main aquifer units and the overburden thickness varies from 5.0 to 16.8 m. The study has shown the usefulness of integrated geophysical methods and techniques in subsurface structural and groundwater development study over the perennial springs in the transition environment between the Nupe Basin and the Southwestern Nigeria Basement complex.
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Wyns, Robert, Jean-Michel Baltassat, Patrick Lachassagne, Anatoly Legchenko, Jacques Vairon, and Francis Mathieu. "Application of proton magnetic resonance soundings to groundwater reserve mapping in weathered basement rocks (Brittany, France)." Bulletin de la Société Géologique de France 175, no. 1 (January 1, 2004): 21–34. http://dx.doi.org/10.2113/175.1.21.
Повний текст джерелаАнотація:
Abstract The Proton Magnetic Resonance (PMR) or Nuclear Magnetic Resonance (NMR) method, coupled with geometrical aquifer modelling, has been used to create a map of groundwater reserves over a 270 km2 study area in a weathered basement setting. Most of the reserves are contained in a stratiform multi-layer aquifer whose geometry is influenced by the weathering front. The depths to the interfaces determined by PMR are considered and validated by comparison with the geometrical approach. Water contents and decay times of the PMR signal for each weathered layer are compared with the hydrogeological model. The results of the study show a decrease in water content from the top downwards for the three main aquifer layers (respectively : unconsolidated alterite, and an upper and a lower fissured zone). The groundwater reserves (80 % in the fissured zone and 20 % in unconsolidated alterite) represent approximately three years of average infiltration.
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Halihan, Todd, Andrew Love, Mark Keppel, Meghan K. M. Dailey, Volmer Berens, and Daniel Wohling. "Evidence for groundwater mixing at Freeling Spring Group, South Australia." Hydrogeology Journal 28, no. 1 (December 4, 2019): 313–23. http://dx.doi.org/10.1007/s10040-019-02069-x.
Повний текст джерелаАнотація:
AbstractWater sampling at springs that are a part of the Freeling Spring Group, South Australia, was used along with electrical resistivity imaging (ERI) data to evaluate the sources and pathways for groundwater to the springs and to find evidence of mixing between the Great Artesian Basin (GAB) aquifer system (Algebuckina Sandstone, Cadna-owie Formation and lateral equivalents) and waters from the adjacent mountain block basement (MB) aquifer. Five springs and a well were used to evaluate spring chemistry; multi-electrode resistivity data were collected along three orientations over the Freeling Spring site. The resistivity data indicate three independent electrically conductive curvilinear features connected to the spring. These features are evidence of mixing at the spring vent similar to what would be predicted from traditional hydraulic flownets. The chemistry of the spring water samples indicates that the water emanating from the Freeling Spring Group is a mixture of waters from both the GAB and the MB aquifers, supporting the geophysical evidence. The data suggest mixing occurs along a fracture in the body of the MB and porous media flow in the GAB beds, but the system is dominated by the GAB flow, which provides approximately 90% of the discharge.
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O, AWALE, NWANKWO L. I, OLADIPO O. I, and LAWAL T. O. "Geo-Electrical Evaluation of Aquifer Characteristics and Groundwater Potential in Sango - Kulende Area, Ilorin, Nigeria." Journal of Applied Science, Information and Computing 1, no. 1 (June 30, 2020): 41–48. http://dx.doi.org/10.59568/jasic-2020-1-1-05.
Повний текст джерелаАнотація:
An electrical resistivity survey involving vertical electrical sounding (VES) has been carried out for groundwater exploration around Sango-Kulende area in Ilorin South Local Government Area of Kwara State, Nigeria. This was performed with a view of determining the aquifer potential and identifying suitable sites where viable boreholes could be dug for long term supply of potable water for the inhabitants of the area. The survey was carried out using a powerful campus ohmega portable resistivity meter while a total of ten (10) VES stations were completed in three evenly spaced profiles using Schlumberger electrode configuration. A maximum half electrode distance of 100m was utilized and the data acquired were analyzed and interpreted with the aid of computer iteration techniques using the Inverse lite and AGCross software. Interpretations of the resistivity data revealed the presence of three interpretable geo-electric layers and aquifer which is mainly an alluvial aquifer. The top lateritic soil has a resistivity value ranging from 150 to 1100Ωm and thickness of 2.0 to 8.0m. The weathered basement has a resistivity ranging from 9.0 to 450Ωm with thickness 10.0 to 25.0m, while the fresh basement layer has resistivities greater than 700 Ωm. The surveyed area is saturated zones and considered to be a good point for locating a groundwater drilling tube of high quality except for VES 4 among all the VES stations.
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Galone, Luciano, Francesco Panzera, Emanuele Colica, Enrique Fucks, Eleonora Carol, Francisco Cellone, Lluís Rivero, Matthew R. Agius, and Sebastiano D’Amico. "A Seismic Monitoring Tool for Tidal-Forced Aquifer Level Changes in the Río de la Plata Coastal Plain, Argentina." Sustainability 16, no. 4 (February 8, 2024): 1432. http://dx.doi.org/10.3390/su16041432.
Повний текст джерелаАнотація:
Ambient seismic noise has gained extensive applications in seismology and plays a pivotal role in environmental seismic studies. This study focuses on the Río de la Plata Coastal Plain, employing the horizontal-to-vertical spectral ratio (HVSR) method on ambient seismic noise records to analyze subsurface dynamics. The region’s hydrogeology is complex, featuring partially interconnected coastal aquifers. The HVSR analysis reveals two peaks, with P0 associated with the sediment-basement interface and P1 linked to a shallower stratigraphic discontinuity. Temporal analysis of P1 highlights cyclical patterns correlated with estuarine levels, suggesting a relationship between variations in seismic velocities and tidal dynamics. Comparisons with aquifer data support the hypothesis that tidal variations influence subsurface mechanical properties, impacting the HVSR function. The study hints at the potential of ambient seismic noise analysis as a non-invasive and cost-effective method for studying coastal aquifers and understanding groundwater dynamics. Ongoing research aims to further explore these relationships for enhanced groundwater resource management.
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Seli, Ahmed Buba, Buba Apagu Ankidawa, and Jackson M. Ishaku. "Dar Zarrouk Parameters for delineation of groundwater potentials in Ganye and Environs, Adamawa State, Northeastern Nigeria." Journal of Tropical Resources and Sustainable Science (JTRSS) 9, no. 1 (August 22, 2021): 20–36. http://dx.doi.org/10.47253/jtrss.v9i1.706.
Повний текст джерелаАнотація:
Groundwater is the main source of water supply in areas in Nigeria including the research area. The research is aimed at delineating groundwater potentials in Ganye and environs using Dar Zarrouk parameters. Fourteen (14) vertical electrical soundings were conducted across the study area in order to determine Dar Zarrouk parameters to determine groundwater potentials in Ganye and environs. The area is underlain by migmatite-gneiss and Pan African granites. Weathered/fractured basement constitute the aquifer type in the area. The aquifer conductivity in the study area range between 0.00871 to 0.032032 ?-1 with mean value of 0.019493 ?-1. The aquifer longitudinal conductance ranges between 0.22246 to 0.759252 with mean value of 0.432846. The transverse resistance range between 627.8721 to 1,857.282 ?m2 with average value of 1,235.854 ?m2. The aquifer hydraulic conductivity range between 6.9314 to 15.562 m/day with mean value of 9.738 m/day while the transmissivity across the study area range between 114.2152 to 378.774 m2/day with mean value of 216.0487 m2/day.