Papers by Gabriel I Obiefuna
The water supply schemes in the study area are based mostly on groundwater which constitute more ... more The water supply schemes in the study area are based mostly on groundwater which constitute more than 70% of the water supply. Most surface water supply dry up during the dry season. The aim of the research is to assess the groundwater potentials in the study area. Seventeen Resistivity depth soundings were carried out in the research area. Vertical electrical sounding technique of Schlumberger array configuration was use to delineate subsurface lithology, identification of aquifer systems and determination of aquifer parameters use for groundwater resource exploration, estimation of supply potential and protective capacities of water sources. The geoelectrical parameters are transverse resistance and longitudinal conductance while aquifer properties are transmissivity and hydraulic conductivity. Hydrogeological field mapping comprising water sampling, measurement of static water level, borehole depth, locations, altitude, physical parameters of groundwater, acquisition of borehole logs and notations on the field topographic map was carried out using appropriate equipment. Aquifer systems of the study site increases in thickness from South to North with Western dominance of confined aquifers and eastern unconfined aquifer dominance. The profiling of the subsurface using borehole logs and resistivity imagery at a location of interest was use to produced geologic map (4 Dimension) of that location with socioeconomic benefits such as anticipation of ground conditions in engineering, groundwater capacity and vulnerability assessment and fundamental understanding of earth materials, processes, and history of that location. This assures its validation for use as geological map by confirmation rather than speculation.
Water is a necessity in every day of our life. In our homes, offices, schools, hospitals, markets... more Water is a necessity in every day of our life. In our homes, offices, schools, hospitals, markets, industries, and even in our personal journey, there is always the need for continual water supply to meet our basic water needs. The research is aimed at delineating groundwater potentials in Alkaleri and environs. The geological field mapping was carried out and different rock types were identified in the study area, which consist of Precambrian basement rocks (Migmatite Gneiss, Hornblende Granite, and Bauchite), and the tertiary sedimentary rock of Kerri-Kerri formation. The vertical electrical sounding method was used to delineate the groundwater potentials in the research area. A total of 30 vertical electrical sounding points was randomly selected and surveyed. The electrode configuration used for the work was Schlumberger array. Fourteen curves were identified in the study area. The result revealed that the transverse resistance values vary from 78.5 Ωm 2 to 7984.9 Ωm 2 with an average value of 2180.534Ωm 2. The values of longitudinal conductance ranges from 0.002258 Ω to 0.74634037 Ω with an average of 0.1713455Ω. The transmissivity values range from 8.89 m 2 /day to 467.2 m 2 /day, average value of 100.3 m 2 /day. The hydraulic conductivity values range from 0.9m/day to 29.6m/day with mean value of 8.3m/day. Aquifer characteristics revealed that transmissivity and hydraulic conductivity showed low potential.
Despite the seriousness of soil erosion and gully formation problems prevalent in Bagadaza area, ... more Despite the seriousness of soil erosion and gully formation problems prevalent in Bagadaza area, limited investigation and researches have been carried out. This research is aimed at investigating the geotechnical properties of soils that contribute to the formation of gully and provides mitigation measures. In order to attain the objectives, different journals, books, previous studies, and papers related to soil investigation and index properties of soils has been reviewed. During field work, visual identification of soils, test pitting, logging, disturbed and undisturbed soil sampling were done. Laboratory test results show that the gully soils are dominated on average by 3.26% Sand, 3.43% Silt and 93.31% Clay. The Liquid Limit varies from 32.5 to 76.6%, and Plasticity Index from 10.54 to 40.06%. The Shrinkage Limits varies from 5.71 to 21.43% and the Free Swell from 40 to 80. The Unified Soil Classification System shows that the gully soils are composed of 11.8% Silt, 17.6% Elastic Silts, 23.5% Fat Clays and 47.1% Lean Clays. The Specific Gravity of the soil samples varies from 2.50 to 2.59, the optimum Moisture Content ranges from 23.1% to 23.2%, while the Maximum Dry Density ranges from 1.16g/cm 3 to 1.57g/cm 3 . The Over Consolidation Ratio of the top soil is greater than 1. The results obtained in this investigation, especially from the Atterberg limit, sieve analysis, compaction test and specific gravity tests, show that the soils are cohesive soils with low dry densities and low specific gravity which mainly contributes the initiation of erosion gully formations in the study area. Of all the preventive and mitigation measures, vegetation is the simple and most effective way of keeping the soil stable. However, a combination of effective structures coupled with vegetation will give rise to a very productive way of combating erosion and gully hazard in the study area.
Water of good quality for domestic, industrial and agricultural purposes is very essential to pub... more Water of good quality for domestic, industrial and agricultural purposes is very essential to public health and overall wellbeing of the people. Domestic and agricultural activities are carried out within the study area without considering the geochemical and biological processes that occur in the groundwater zone. The water quality of Jalingo Area NE Nigeria was investigated with the aim of determining its suitability for domestic, industrial and agricultural purposes. A total of 50 water samples were collected from surface water and groundwater sources which were analysed using standard methods; Atomic Absorption spectrophotometry for cations and conventional titration for anions. The water was characterized employing chemical indicators such as pH, sulphate, chloride and nitrate and the results indicate that most groundwater samples and some surface water samples are largely suitable for human consumption. Most of the surface water samples revealed total coliform bacteria values above the international permissible limits whereas most of the groundwater samples indicate values that are less than the international permissible limits. The chemistry of the different water sources suggests that alkaline earths (Ca+Mg) significantly exceed the alkalis (Na+K) and weak acids (HCO3+CO3) exceed the strong acids (CI+SO4) suggesting the dominance of CO3 weathering followed by silicate weathering. Hydrogeochemical studies disclosed the Ca 2+-SO4 2-, Ca 2+-CI-, Na +-HCO3-and Na +-Cl-as the dominant ion types for surface water samples and Na +-HCO3 2-and Ca 2+-HCO3 as the major ions for groundwater samples. The homogenous composition of groundwater indicates a common origin and source whereas the nonhomogenous composition of surface water samples reveals active groundwater mixing and significant water-rock interaction, the irrigation indices determined revealed 642 values of TDS (<421 mg/l), SAR (<10), EC (<750 µS/cm) and TH (<250 mg/l) obtained for most of the water sources are found to be within the safe permissible limits for irrigation. However, some samples which displayed values of MAR (> 50%), PI (<25%), KR (>1.00) and SSP (>75%) suggest salinity hazards and should be treated before use. The groundwater samples are generally slightly acidic, largely soft, with fairly low to moderate concentrations of dissolved solids that fall within the international limits for drinking domestic and irrigation. The concentration of nitrate in about 71% of the water samples is higher than the recommended limits of 0.3 mg/l and 10 mg/l respectively should be treated before use.
The study area witnessed expansion, growth and developmental activities which results in poor wat... more The study area witnessed expansion, growth and developmental activities which results in poor water quality supply, which necessitated this research work that is aimed at characterizing the groundwater on the basis of chemistry in Alkaleri and environs. A total of 40 water samples were taken from hand dug wells and boreholes. The physical and chemical parameters were determined using standard methods. The results of the 40 water samples analyzed revealed that only iron and Manganese exceeded the World Health Organization permissible limit for water consumption. Iron ranges from 0.21 to 1.02mg/l with the mean of 0.51mg/l and standard deviation of 0.1,7 the high concentration of iron in the samples is due to ferromagnesium minerals which are the major mineral in Basaltic and Kerri-Kerri Sandstone. Manganese ranges from 0 to 0.06mg/l with the mean value of 0.003mg/l and standard deviation of 0.009, this showed that the water has been in contact with rock for a longer time. Piper trilinear diagram was plotted and results indicated that most samples fall in the region of Ca-Mg-HCO3 facies which is the dominant water type. The second water type is Ca-Mg-SO4-Cl. This water type is regarded as water of intermediate composition that evolved through simple hydrochemical mixing influenced by reversed cation exchange. Principal Component Analysis and Hierarchical Cluster Analysis revealed natural mineralization, salinity of the water, weathering and rock-water interaction, temporary hardness of groundwater, caused by leaching of bed rock materials and anthropogenic contamination. The result of the Water Quality Index showed that 2.5% of the water samples revealed poor water quality of grade C, good quality water of grade B constitute. 67.5%, and Excellent Water quality of grade A constitutes 30%.
The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to c... more The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to consistent flooding in the area and the demand for water for agricultural and domestic purposes. It is therefore very important to carryout adequate pre-construction investigations aimed at investigating the suitability of the area for dam siting. Geophysical and geotechnical investigation was carried out along River Loko. Detailed geologic mapping carried out showed that the area is 75% covered with alluvium while basalts and finemedium grained granites underly the smaller portion of the area. A total of 10 Vertical Electrical Soundings were carried out using Schlumberger array. Disturbed soil samples were collected at a depth interval of 0.3m, from the surface to 1.2m, from three trial pits. Results of the geophysical survey show a 3 -4-layer model consisting of H, HA, AH-type curves, interpreted with Interpex IX1D software. Results of the particle size distribution show that most of the samples are very uniform having a coefficient of uniformity of less than 5 according to (AASHTO) classification all the soil samples collected at the three trial pits are specifically A-3 soil group, which indicates that the material are fine sands. The Atterberg limit results indicate that most of the soil samples fall within the medium plasticity index. Soils with high plasticity (22.35) and medium plasticity ( ) are usually semi-impervious to impervious, hence, suitable for dam foundation. The result of the unsoaked CBR compared with the standard, according to AASHTO, indicates that all samples fall under 7-20 which shows a general rating as 'fairly soil' and can be used as 'sub-base'. Compaction results show that for Pit 1, the sample at 0.3m, with MDD 1700kg/m 3 at OMC 20.0%, is the best sample. For Pit 2, the sample at 0.9m, with MDD 2400kg/m 3 at OMC 10.0%, is the best, and for Pit 3, the sample at 0.3m, with MDD 1800kg/m 3 at OMC 11.0%, is the best. The interpretations of the undrained shear strength result indicate that all the samples have 'soft consistency' since their values range from 23.0 to 25.7 KN/m 2 . Based on the availability of construction material, perennial discharge from the river in addition to suitable geology and engineering properties, the area is feasible for an earth dam construction. Deep foundation is recommended for a massive rock filled dam, and some remediation is required in the design process to reduce the threat posed by thin fractures which may possibly cause subsurface seepage.
The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to c... more The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to consistent flooding in the area and the demand for water for agricultural and domestic purposes. It is therefore very important to carryout adequate pre-construction investigations aimed at investigating the suitability of the area for dam siting. Geophysical and geotechnical investigation was carried out along River Loko. Detailed geologic mapping carried out showed that the area is 75% covered with alluvium while basalts and finemedium grained granites underly the smaller portion of the area. A total of 10 Vertical Electrical Soundings were carried out using Schlumberger array. Disturbed soil samples were collected at a depth interval of 0.3m, from the surface to 1.2m, from three trial pits. Results of the geophysical survey show a 3-4-layer model consisting of H, HA, AH-type curves, interpreted with Interpex IX1D software. Results of the particle size distribution show that most of the samples are very uniform having a coefficient of uniformity of less than 5 according to (AASHTO) classification all the soil samples collected at the three trial pits are specifically A-3 soil group, which indicates that the material are fine sands. The Atterberg limit results indicate that most of the soil samples fall within the medium plasticity index. Soils with high plasticity (22.35) and medium plasticity (9) are usually semi-impervious to impervious, hence, suitable for dam foundation. The result of the unsoaked CBR compared with the standard, according to AASHTO, indicates that all samples fall under 7-20 which shows a general rating as 'fairly soil' and can be used as 'sub-base'. Compaction results show that for Pit 1, the sample at 0.3m, with MDD 1700kg/m 3 at OMC 20.0%, is the best sample. For Pit 2, the sample at 0.9m, with MDD 2400kg/m 3 at OMC 10.0%, is the best, and for Pit 3, the sample at 0.3m, with MDD 1800kg/m 3 at OMC 11.0%, is the best. The interpretations of the undrained shear strength result indicate that all the samples have 'soft consistency' since their values range from 23.0 to 25.7 KN/m 2. Based on the availability of construction material, perennial discharge from the river in addition to suitable geology and engineering properties, the area is feasible for an earth dam construction. Deep foundation is recommended for a massive rock filled dam, and some remediation is required in the design process to reduce the threat posed by thin fractures which may possibly cause subsurface seepage.
The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to c... more The need for dam construction in the Loko area of northeastern Nigeria becomes necessary due to consistent flooding in the area and the demand for water for agricultural and domestic purposes. It is therefore very important to carryout adequate pre-construction investigations aimed at investigating the suitability of the area for dam siting. Geophysical and geotechnical investigation was carried out along River Loko. Detailed geologic mapping carried out showed that the area is 75% covered with alluvium while basalts and finemedium grained granites underly the smaller portion of the area. A total of 10 Vertical Electrical Soundings were carried out using Schlumberger array. Disturbed soil samples were collected at a depth interval of 0.3m, from the surface to 1.2m, from three trial pits. Results of the geophysical survey show a 3 -4-layer model consisting of H, HA, AH-type curves, interpreted with Interpex IX1D software. Results of the particle size distribution show that most of the samples are very uniform having a coefficient of uniformity of less than 5 according to (AASHTO) classification all the soil samples collected at the three trial pits are specifically A-3 soil group, which indicates that the material are fine sands. The Atterberg limit results indicate that most of the soil samples fall within the medium plasticity index. Soils with high plasticity (22.35) and medium plasticity ( ) are usually semi-impervious to impervious, hence, suitable for dam foundation. The result of the unsoaked CBR compared with the standard, according to AASHTO, indicates that all samples fall under 7-20 which shows a general rating as 'fairly soil' and can be used as 'sub-base'. Compaction results show that for Pit 1, the sample at 0.3m, with MDD 1700kg/m 3 at OMC 20.0%, is the best sample. For Pit 2, the sample at 0.9m, with MDD 2400kg/m 3 at OMC 10.0%, is the best, and for Pit 3, the sample at 0.3m, with MDD 1800kg/m 3 at OMC 11.0%, is the best. The interpretations of the undrained shear strength result indicate that all the samples have 'soft consistency' since their values range from 23.0 to 25.7 KN/m 2 . Based on the availability of construction material, perennial discharge from the river in addition to suitable geology and engineering properties, the area is feasible for an earth dam construction. Deep foundation is recommended for a massive rock filled dam, and some remediation is required in the design process to reduce the threat posed by thin fractures which may possibly cause subsurface seepage.
The geophysical and geotechnical techniques were applied in order to determine the immediate and ... more The geophysical and geotechnical techniques were applied in order to determine the immediate and remote causes of a failed dam project in Cham area NE Nigeria. Details of site investigation for the Cham dam are presented. Geologically, the dam-site rests on the geologically disturbed Yolde Formation. The course of the Cham River is structurally controlled by the underlying strike-slip and dip-slip faults. Ground geological investigation revealed the presence of joints, faults and associated slicken-sides and shear zones as well as desiccation cracks within the rock formations. Geophysical investigations confirms that these joints and fault zone extends more than 35 meters below the river beds. It also revealed the presence of shally clay, lateritic dark clay, fissile shale and friable siltstone to depths of more than 35 meters below the river bed. Laboratory studies of the engineering properties of the rocks disclosed a mean optimum moisture content of 14.6% at a mean maximum dry density of 1.80 mg/m 3 , mean plasticity index value of 34.5% and a mean CBR value of 3% suggesting a highly weathered, plastic, friable and structurally weak rocks. These studies helped in explaining both the immediate and remote causes of the failed dam project.
Assessment of Shallow Groundwater Quality of Michika Area, NE Nigeria
Groundwater forms the only reliable source of water supply and faces a growing demand for irrigat... more Groundwater forms the only reliable source of water supply and faces a growing demand for irrigated agriculture and domestic uses especially in semiarid and arid regions. The suitability of groundwater for irrigation depends on the water quality characteristics that ensure maximum yield under good soil and water management. Objective: The objective of this study is to assess the shallow groundwater of Michika area of Nigeria for its applicability in irrigation. Materials and Methods: In this study groundwater samples were collected from forty wells and were subjected to chemical analyses employing standard methods (Atomic Adsorption Spectrophotometry for cations and conventional titration for anions). The chemical parameters obtained were used to compute the irrigation indices which were interpreted using SPSSX software program indicating inter-element and irrigation indices relationship. The statistical values of minimum and maximum chemical parameters and irrigation indices were u...
The aim of the study is to characterize groundwater in semiarid Yola area of northeastern Nigeria... more The aim of the study is to characterize groundwater in semiarid Yola area of northeastern Nigeria employing chemical indicators. The dissolution of halite, gypsum, dolomite and calcite determines Na + , Mg 2+ , Ca 2+ , ClG, SO 4 2and HCO 3 G chemistry while other processes such as evaporation and ion exchange also influence the water composition. Surface water and groundwater chemistry data enabled geographical zones and chemical types to be differentiated. Groundwater in the study area is slightly acidic to neutral in nature. Chemistry of groundwater suggests that alkaline earths (Ca+Mg) significantly exceed the alkalis (Na+K) and weak acids (HCO 3 +CO 3) exceed the strong acids (Cl+SO 4), suggesting the dominance of CO 3 weathering followed by silicate weathering. Hydrogeochemical studies disclosed that Na +-HCO 3 G and Na +-ClG are the dominant ion types for the shallow groundwater (<25 m), Mg 2+-ClG, Mg 2+-HCO 3 G and Na +-ClG for the deep groundwater (>25 m) and Na +-ClG for the surface water bodies. A high positive correlation (r 2 = 0.87) between Na + and ClG suggests that the salinity of groundwater is due to intermixing of two or more groundwater bodies with different hydrochemical compositions. Chemical fertilizers and anthropogenic activities are contributing to sulphate, nitrate and chloride concentrations measured in some surface water and groundwater samples in the study area as evidenced by the relatively high sulphate, nitrate and chloride concentrations. Most of the groundwater samples are suitable for domestic purposes.
International Journal of Scientific & Technology Research, Apr 25, 2018
The aim of this study is to determine the geochemical and mineralogical composition of granitic r... more The aim of this study is to determine the geochemical and mineralogical composition of granitic rock deposit of Michika area of northeastern Nigeria. Detailed geological mapping of an area of 188.5 Km2 around Michika area has been mapped on a scale of 1: 50,000. The mapping revealed that the area is underlain by granitic rocks of Pan African Age. These are grouped into three types: coarse grained biotite granites, coarse porphyritic granites and medium grained granites which are intruded by the new basaltic rocks of Tertiary Age. A plot of Rose Diagrams indicate they trend in the NE-SW and NW-SE directions and occurs as irregular or massive bodies, veins and sometimes as a cross-cutting discordant dykes. The fracture ranges from about 5 cm to about 2 meters. Seven samples were collected at different locations representing the three types for petrographic analyses. Petrographic studies show that the samples are essentially composed of quartz, feldspar, mica and iron oxide. Twenty samples were analyzed geochemically using XRF method to determine some major oxides which include SiO2, Al2O3, K2O, Fe2O3 and CaO. The SiO2 content are mainly (70.58%), Al2O3 (14.30%), K2O (5.44%), Fe2O3 (2.73%) and CaO (2.62%) were obtained for the samples. The results indicate that granitic bodies of the Older Granites that underlie the study area are strongly peraluminous calcalkaline igneous series that are of both lithospheric origin or are associated with subduction related areas.
Determining Potential Areas of Groundwater Occurrences Using Remote Sensing Techniques: A Case Study of Mubi Area, Northeast, Nigeria
This work involves determining potential areas of groundwater occurrences using remote sensing te... more This work involves determining potential areas of groundwater occurrences using remote sensing techniques in parts of Mubi area of Northeast, Nigeria. The study area is underlain by Biotite-granite, Migmatites which is subsequently overlain by the Recent and Terraced Alluvium. The lineament\fractures analysis and statistical analysis of the Satellite imagery shows that the study area has swarms of fractures in addition to highly weathered rocks. The results from the lineament\fracture analysis intergrated together with existing geological map following fieldwork (ground truthing) showed potential areas of groundwater occurrence. This study has demonstrated that the application of remote sensing technology or groundwater assessment can lead to recognition of important hydro geological units. It has led to the delineation of areas where groundwater occurrence is most promising, and consequently where further geophysical surveys can be concentrated. INTRODUCTION Groundwater is the water that occurs in the pores of the sub-surface rock formation. The movement of groundwater depends on two important physical properties of the rock material namely: Porosity and Permeability. Groundwater can be found in areas underlain by sedimentary and basement complex [crystalline] rocks. Targeting of groundwater in basement is not an easy task. Here groundwater occurrence is limited to weathered basement aquifers and the fractured zones. The aquifer system in the basement complex rock formations are complex. Different portions exhibit different permeability and porosity and therefore heterogeneous. Thus, crystalline rocks are multiple aquifer system instead of a single homogenous aquifer (Ogunjobi, 1983).
Determining Potential Areas of Groundwater Occurrences Using Remote Sensing Techniques: A Case Study of Mubi Area, Northeast, Nigeria
This work involves determining potential areas of groundwater occurrences using remote sensing te... more This work involves determining potential areas of groundwater occurrences using remote sensing techniques in parts of Mubi area of Northeast, Nigeria. The study area is underlain by Biotite-granite, Migmatites which is subsequently overlain by the Recent and Terraced Alluvium. The lineament\fractures analysis and statistical analysis of the Satellite imagery shows that the study area has swarms of fractures in addition to highly weathered rocks. The results from the lineament\fracture analysis intergrated together with existing geological map following fieldwork (ground truthing) showed potential areas of groundwater occurrence. This study has demonstrated that the application of remote sensing technology or groundwater assessment can lead to recognition of important hydro geological units. It has led to the delineation of areas where groundwater occurrence is most promising, and consequently where further geophysical surveys can be concentrated. INTRODUCTION Groundwater is the water that occurs in the pores of the sub-surface rock formation. The movement of groundwater depends on two important physical properties of the rock material namely: Porosity and Permeability. Groundwater can be found in areas underlain by sedimentary and basement complex [crystalline] rocks. Targeting of groundwater in basement is not an easy task. Here groundwater occurrence is limited to weathered basement aquifers and the fractured zones. The aquifer system in the basement complex rock formations are complex. Different portions exhibit different permeability and porosity and therefore heterogeneous. Thus, crystalline rocks are multiple aquifer system instead of a single homogenous aquifer (Ogunjobi, 1983).
Journal of Applied Sciences and Environmental Management, 2010
Chemical speciation of some metal ions in groundwaters of Yola area using geochemical model were ... more Chemical speciation of some metal ions in groundwaters of Yola area using geochemical model were carried out to determine the water quality of the area using the PHREEQC speciation model. The study findings based on model calculations indicated that free Na + , Ca 2+ , Mg 2+ and K + ions are present and the consequent bioavailability are 95.83% to 99.84% at the pH ranges of 6.1 to 7.8 of the tested wells. Iron as free Fe 2+ was bioavailable at 46.53% to 79.37% of the total iron. The lower values of free Fe 2+ ions are related to the organic complexation of the ions. The model findings suggest that Fe 2+ levels present a health risks in some water samples. The result also indicate that the concentration of Na + , Ca 2+ , Mg 2+ and K + at such level would be available for uptake by plants, animals and humans. @ JASEM 1 GABRIEL IKE OBIEFUNA; 2 DONATUS MADUKA ORAZULIKE Table 2: Result of PHREEQC output file containing activities and concentrations of some ionic species in Shallow Groundwater samples (After Obiefuna in Preparation) Species Concentration mg/l Activity mg/l Species Concentration mg/l Activity Ca 2 +
A geotechnical evaluation of some soils in Numan, Adamawa, North –East, Nigeria has been carried ... more A geotechnical evaluation of some soils in Numan, Adamawa, North –East, Nigeria has been carried out. This was done to determine the suitability of the soils for use as sub-grade/filling, sub-base and base course materials for road construction. The samples were collected from five different areas, at surface and sub-surface levels. The areas are New Demsa, Farei, Dowaya, Numan Town and Imbru. The soil samples were subjected to laboratory investigations in conformity with the American Association of State Highway and Transportation (AASHTO) and the Bristish Standard Institution (BSI) Standard specifications. Results of the geotechnical tests indicate that the proportion passing the BS sieve NO.200 ranges from 20. 92% to 39. 02% whereas plasticity index and consistency index ranges from 14.05 to 22. 01 and 1. 42% to 2. 16% respectively. The compaction test result revealed an optimum Moisture Content (O.M.C) Value of 11. 60% and a maximum Dry Density (M.D.D) Value ranging from 91g/cm&...
An assessment of the geological and geotechnical parameters as causative agents in the formation ... more An assessment of the geological and geotechnical parameters as causative agents in the formation of gullies in Wuro Bayare area of northeastern Nigeria is presented. Field geological study of the study area revealed that the area is underlain by basement rocks. The soils in the area are product of in-situ weathering of the underlying basement rocks. The results of sieve analysis shows that the soils at the gully sites have sorting values ranging between 0.42 and 2.3, coefficient of uniformity values ranging between 0.02 and 200, coefficient of curvature values ranging between 0.0125 and 0.23 and also the constanthydraulic values (Kvalues) is use to know the bottom erosion ranges. These indicate that the soils are poorly to well-sorted in places. The plasticity indices values ranges between 9.9 and 5.5 with a mean value of about 20 indicates soils of moderate to highly plasticity, slight dry strength and easily friable. Values of Maximum Dry Density (MDD) ranging between 2.15 and1.83 g/cm 3 at Optimum Moisture Contents (OMC) of between 12.4 and 6.4% reveals that the soils were generally lose. From the geotechnical analysis results, commendations for erosions control such as; construction of drainages, grouting concrete rip-raps and afforestation were suggested.
The Hydrochemical Characteristics and Evolution of
Evaluation of corrosion and encrustation potentials of boreholes in Yola area NE Nigeria
An assessment of the geological and geotechnical parameters as causative agents in the formation ... more An assessment of the geological and geotechnical parameters as causative agents in the formation of gullies in Wuro Bayare area of northeastern Nigeria is presented. Field geological study of the study area revealed that the area is underlain by basement rocks. The soils in the area are product of in-situ weathering of the underlying basement rocks. The results of sieve analysis shows that the soils at the gully sites have sorting values ranging between 0.42 and 2.3, coefficient of uniformity values ranging between 0.02 and 200, coefficient of curvature values ranging between 0.0125 and 0.23 and also the constanthydraulic values (K- values) is use to know the bottom erosion ranges. These indicate that the soils are poorly to well-sorted in places. The plasticity indices values ranges between 9.9 and 5.5 with a mean value of about 20 indicates soils of moderate to highly plasticity, slight dry strength and easily friable. Values of Maximum Dry Density (MDD) ranging between 2.15 and1....
Uploads
Papers by Gabriel I Obiefuna