Journal Articles http://repository.fuoye.edu.ng:80/handle/123456789/79 2026-04-16T23:21:21Z 2026-04-16T23:21:21Z AKINRINADE Opeyemi Joshua, OLABODE Oladunjoye Peter http://repository.fuoye.edu.ng:80/handle/123456789/1111 2015-11-28T19:13:28Z 2015-11-28T00:00:00Z

Title: Integrated Geophysical Approach to Aquifer Delineation in Crystalline Basement Environment Authors: AKINRINADE Opeyemi Joshua, OLABODE Oladunjoye Peter Abstract: Aquifer delineation and characterization could be somewhat challenging in Crystalline Basement Complex environment, where they are associated with either saturated weathered Basement or fractured Basement. Increasing demand for water occasioned by domestic and industrial purposes resulted in delineation and characterization of aquifer properties at a site within the crystalline basement environment, where two boreholes have been drilled (BH1 and BH2). Very Low Frequency Electromagnetic (VLF-EM) and Electrical resistivity methods were used. Twelve (12) VLF-EM profiles of length 120 – 160 m, with 10 m station separation oriented in east-west direction and twenty-five (25) VES stations were occupied. Three peak positive raw/filtered real VLF-EM anomalies identified are presumed to be water-filled fractures or faults; thus implying possible locations suitable for groundwater development. Four geoelectric layers were delineated namely: top soil, clayey sand/sandy clay, weathered layer and basement rock. The weathered layer is characterized by resistivity values which range from 28 to 1309 Ωm, and thickness values of 2.9 to 15.1 m. Longitudinal unit conductance (S), Transverse unit resistance (T), and coefficient of Anisotropy (λ) have values ranging from 0.03 – 0.16 mhos, 382 – 8517 Ωm2, and 1.05 – 2.24 respectively. These results are indicative of the aquifer protective capacity, hydraulic conductivity, aquifer productivity and hydrogeologic significance. BH1 failed because it was drilled into the weathered basement at a location characterized by fairly low transverse resistance, while BH2 was drilled into a localized fractured basement with fairly high recharge attributed to extent of fracture network, high transverse resistance and coefficient of anisotropy. Thus, fracture network and its depth extent are of great importance in selecting fractured basement aquifer as groundwater development site. Integration of electromagnetic profiling with electrical resistivity methods has shown to be complimentary tools in determination of groundwater potential and reduces uncertainties in predicting drillable positions. Robust assessment of the weathered basement and fractured basement aquifer parameters has assisted in locating productive borehole position in basement complex environment. This creates opportunities for efficient resources management, and reduces the risk of sinking unproductive boreholes.

2015-11-28T00:00:00Z Dare-Alao, Damilola http://repository.fuoye.edu.ng:80/handle/123456789/978 2015-09-21T11:59:47Z 2013-04-22T00:00:00Z

Title: Geospatial modeling of electricity distribution network Authors: Dare-Alao, Damilola

2013-04-22T00:00:00Z OLADAPO, MICHAEL ILESANMI AYENI, OLAYIWOLA GRACE http://repository.fuoye.edu.ng:80/handle/123456789/975 2015-09-17T11:14:38Z 2013-07-16T00:00:00Z

Title: Hydrogeophysical investigation in selected parts of Irepodun/Ifelodun Local Government Area of Ekiti State, Southwestern Nigeria Authors: OLADAPO, MICHAEL ILESANMI; AYENI, OLAYIWOLA GRACE Abstract: Hydrogeophysical studies have been undertaken at Irepodun/Ifelodun local government area of Ekiti State, Nigeria. The area is underlain by the Basement Complex rocks. The study involved very low frequency electromagnetic (VLF-EM) and electrical resistivity methods. The results are presented as profiles, sections, curves, charts and maps. VLF-EM anomalies were evaluated using geoelectric soundings. Geoelectric sounding results enabled the determination of overburden thickness, transverse unit resistance, longitudinal unit conductance and coefficient of anisotropy (). Overburden thickness zones of 45 to 55 m were classified as high, 15 to 45 m as moderate and values less than 15 m as low. Afao, Obo, Iyin, Araromi, Iketun and Igede are of moderate to high groundwater potential, while other towns are of low groundwater potential. Longitudinal unit conductance showed that the area is characterized by sequence of good, moderate and weak groundwater protective capacities. Computed λ values revealed that the northern flank (Esure and Iropora) are underlain by charnockite of low λ (1.0 - 1.1) with other areas of high λ (1.1 - 2.1) underlain by granite and migmatite gneiss. Groundwater development is feasible in Araromi, Afao, Iyin, Obo, Iketun and Igede but marginally feasible in the other towns. Thus, groundwater potential of Irepodun/Ifelodun local government area is generally low

2013-07-16T00:00:00Z OGUNGBEMI, OLUWASEUN SAMUEL BADMUS, O. G AYENI, OLAYIWOLA GRACE OLOGE, OLUWATOYIN http://repository.fuoye.edu.ng:80/handle/123456789/974 2015-09-17T11:09:25Z 2013-11-01T00:00:00Z

Title: Geoelectric Investigation of Aquifer Vulnerability within Afe Babalola University, Ado –Ekiti, Southwestern Nigeria. Authors: OGUNGBEMI, OLUWASEUN SAMUEL; BADMUS, O. G; AYENI, OLAYIWOLA GRACE; OLOGE, OLUWATOYIN Abstract: Many investigation techniques are commonly employed with the aim of estimating the spatial distribution of transmissivity and protective capacity of groundwater resources. Unfortunately, the conventional methods for the determination of hydraulic parameters such as pumping tests, permeameter measurements and grain size analysis are intrusive and relatively expensive. A non-intrusive and less-expensive geoelectric investigation involving vertical electrical sounding was carried out in some parts of the campus of Afe Babalola University, Ado Ekiti, Ekiti State, Nigeria. A total of fifty-nine (59) vertical electrical sounding (VES) data were acquired using R 50 D.C. resistivity meter within the campus which is underlain by the Precambrian basement rock of southwestern Nigeria. Following the interpretation of the VES data, maps and 2D-sections were generated. The geoelectric sections enabled the subsurface to be characterized into five geoelectric layers namely: Topsoil, clayey/sandy-clay, weathered layer, fractured basement and fresh basement. The assessment and analysis of the materials above the aquifers showed that longitudinal conductance (S) values ranged from 0.08438 to 0.73449 mhos; thus the area is classified into weak (0.1 – 0.19 mhos), moderate (0.2 – 0.69 mhos) and good protective capacity (0.7 mhos and above). The major aquifer delineated is the weathered/fractured basement aquifers. These aquifers are characterized by thick overburden, moderate/good protective capacity, moderate to relatively high value coefficients of anisotropy and low transverse unit resistance. This suggests that the materials above the aquifers act as seal, thus protecting the major aquiferous units. However, the aquifer matrix itself is relatively permeable. Areas with weak protective capacity are therefore vulnerable to infiltration of polluting fluid.

2013-11-01T00:00:00Z Olabode O. P., Enikanselu P. A. http://repository.fuoye.edu.ng:80/handle/123456789/962 2015-09-07T12:49:58Z 2008-01-01T00:00:00Z

Title: Analysis of Seismic Time-Depth Conversion Using Geostatistically- Derived Average Authors: Olabode O. P., Enikanselu P. A. Abstract: Geostatistical techniques were used for seismic time-depth conversion over “Labod” field offshore Western Niger Delta Basin with the aid of surface seismic and borehole data. Gamma ray and resistivity logs in four exploratory wells were utilized to delineate formation lithologies (facies) and formation fluid content. The target horizon B (top of sand 2) was selected for seismic structural mapping. Two major faults (F1, F2) and three minor faults (F3, F4 and F5) were identified and interpreted on the seismic sections. Average velocities were first calculated from sonic logs. Geostatistical techniques - Kriging with External Drift (KED) and Simple Kriging - were employed to generate average velocity models used to convert the target B seismic time surface to depth in and away from well locations and depth maps were generated. The results of maximum percentage deviation computed among field-observed and computed depths were lower than 5% suggesting that the average velocity values estimated away from wells were reliable and applicable especially in areas where there is scarcity of well information. The Kriging with External Drift (KED) technique is particularly recommended because of the higher accuracy and denser data coverage. Finally, the method is cost effective because only few wells are required to achieve the expected results.

2008-01-01T00:00:00Z Bamidele, Odunayo E. Akintorinwa, O. J. http://repository.fuoye.edu.ng:80/handle/123456789/953 2015-08-25T15:15:49Z 2014-01-01T00:00:00Z

Title: Development of Computer Software for Seismic Refraction Data Interpretation and Engineering Parameters Determination Authors: Bamidele, Odunayo E.; Akintorinwa, O. J. Abstract: Computer software was developed for seismic refraction data interpretation and computation of engineering parameters as a means to ease the problem of cumbersomeness of the manual interpretation of seismic refraction data and computation of engineering parameters by adopting seismic refraction method of investigation. Necessary equations for the program were compiled, and the program algorithms were developed, fed into a computer interpreter, debugged and run. The program algorithm was written with Visual Basic Programming Language and the software was designed using Visual Basic tools.The software accepts and interprete Single On Shot and On and Reverse Shot seismic refraction data for planar and dipping interface. The developed software plots T-X graph and compute the layer velocities and thicknesses. Engineering parameters such as Fracture Frequency (n), Rock Quality Designation (RQD), Bulk and Young modulus and Poisson ratio (σ) which are used in subsurface engineering evaluation can also be computed using the software.Seismic refraction data for both planar and dipping interface were obtained and used in testing the efficiency of the software and the results correlate with that of manual interpretation and computation.

2014-01-01T00:00:00Z Izzy M. Kutasov, Lev V. Eppelbaum http://repository.fuoye.edu.ng:80/handle/123456789/148 2016-01-15T13:45:43Z 2012-10-07T00:00:00Z

Title: Geothermal Investigations in Permafrost Regions— The Duration of Temperature Monitoring after Wellbores Shut-In Authors: Izzy M. Kutasov, Lev V. Eppelbaum Abstract: The most important data on the thermal regime of the Earth’s interior come from temperature measurements in deep boreholes. The drilling process greatly alters the temperature field of formations surrounding the wellbore. In perma- frost regions, due to thawing of the formation surrounding the wellbore during drilling, representative data can be ob- tained only by repeated observations over a long period of time (up to 10 years). Usually a number of temperature logs (3 - 10) are taken after the well’s shut-in. Significant expenses (manpower, transportation) are required to monitor the temperature regime of deep wells. In this paper we show that in most of the cases (when the time of refreezing forma- tions is less than the shut-in time) two temperature logs are sufficient to predict formations temperatures during shut-in, to determine the geothermal gradients, and to evaluate the thickness of the permafrost zone. Thus the cost of monitoring the temperature regime of deep wells after shut-in can be drastically reduced. A simple method to process field data (for the well sections below and above the permafrost base) is presented. Temperature logs conducted in two wells were used to demonstrate utilization of this method. Description: The most important data on the thermal regime of the Earth’s interior come from temperature measurements in deep boreholes. The drilling process greatly alters the temperature field of formations surrounding the wellbore. In perma- frost regions, due to thawing of the formation surrounding the wellbore during drilling, representative data can be ob- tained only by repeated observations over a long period of time (up to 10 years). Usually a number of temperature logs (3 - 10) are taken after the well’s shut-in. Significant expenses (manpower, transportation) are required to monitor the temperature regime of deep wells. In this paper we show that in most of the cases (when the time of refreezing forma- tions is less than the shut-in time) two temperature logs are sufficient to predict formations temperatures during shut-in, to determine the geothermal gradients, and to evaluate the thickness of the permafrost zone. Thus the cost of monitoring the temperature regime of deep wells after shut-in can be drastically reduced. A simple method to process field data (for the well sections below and above the permafrost base) is presented. Temperature logs conducted in two wells were used to demonstrate utilization of this method.

2012-10-07T00:00:00Z K. F. KASEKE, A. J. MILLS K. ESLER, J. HENSCHEL M. K. SEELY, R. BROWN http://repository.fuoye.edu.ng:80/handle/123456789/139 2016-01-15T13:46:24Z 2012-04-01T00:00:00Z

Title: Spatial Variation of ‘‘Non-Rainfall’’ Water Input and the Effect of Mechanical Soil Crusts on Input and Evaporation Authors: K. F. KASEKE, A. J. MILLS; K. ESLER, J. HENSCHEL; M. K. SEELY, R. BROWN Abstract: ‘‘Non-rainfall’’ water is important to the soil water balance and ecology of arid ecosystems. A component of this ‘‘non-rainfall’’ water in the Namib Desert, fog, exhibits spatial variation implying variability in composition and significance of each vector (dew, fog, vapour adsorption) to ecology at different locations. The composition of ‘‘non -rainfall’’ water input directly into soil was investigated at two sites in the Central Namib Desert, Kleinberg and Gobabeb. Results showed spatial variation in composition between the sites, although vapour adsorption dominated input at both sites. Fog contributed more to total ‘‘non rainfall’’ atmospheric water closer to the coast (Kleinberg) compared to further inland (Gobabeb) but was lower than expected at both sites. Absolute values of fog input at both sites showed the opposite trend, Kleinberg 0.38 mm per night compared to Gobabeb 8.7 mm per night. This difference was attributed to the development of a mechanical crust on the soil surface at Kleinberg, which resulted in a significant reduction of vapour adsorption compared to Gobabeb. The crust also led to a significant reduction in evaporation from the sample at Kleinberg compared to the one at Gobabeb. Ecological differences between the two sites can be attributed to the development of the soil crust on the sample at Kleinberg and not on the sample at Gobabeb.

2012-04-01T00:00:00Z