Emmanuel K Anakwuba - Academia.edu (original) (raw)

Papers by Emmanuel K Anakwuba

Pure and Applied Geophysics, Jan 31, 2012

ABSTRACT Fractures are deformations in rocks with discontinuity. They are important in a number o... more ABSTRACT Fractures are deformations in rocks with discontinuity. They are important in a number of ways. Their presence significantly influences the strength and engineering properties as well as the hydraulic characteristics of rocks. Fractures may extend to the surface where they are observed and studied at outcrops. On the other hand, they may terminate in the subsurface or may be covered by overburden which makes them impossible to be studied and characterized at the ground surface. There has been an increasing interest in the location and characterization of fractures by earth scientists, engineers and other scientists, both at the surface and the subsurface. However, the unavailability or inaccessibility of good outcrops makes it imperative to develop methods and tools for studying fractures in the subsurface. Geophysical methods such as the resistivity methods have been very useful in this regard. The Azimuthal Square Array Resistivity Survey was used in this project to locate and characterize subsurface fractures in the crystalline rocks at Igarra. Results from the analysis and interpretation of the field data showed that the dominant fracture strike orientation is in the NNW–SSE direction. This compares well with the results of surface geologic mapping data which gave the general fracture strike orientation as N–S; however, the major large and extensive fractures are striking NNW–SSE. This information is very useful in modeling groundwater flow and contaminant transport; planning proper waste management programs as well as the Environmental Impact Assessment analysis for the study area. This study once more illustrates the satisfactory use of non-invasive geophysical methods in characterizing fractures in the subsurface especially where quality outcrops are not available or inaccessible.

Research journal of environmental and earth sciences, Aug 10, 2011

Total field aeromagnetic anomalies over Okigwe area have been evaluated in order to map lineament... more Total field aeromagnetic anomalies over Okigwe area have been evaluated in order to map lineaments and estimate the depths to basement (sedimentary thicknesses). Aeromagnetic contour map of Okigwe (Sheet 312) was acquired, digitized and analyzed. Regional-residual separation and Slope methods were applied. The magnetic lineament map shows major geologic lineaments trending in NE-SW direction with minor ones trending in NW-SE direction. The major trend is in conformity with the trend of the Benue Tough. Visual study of the map shows presence of igneous intrusives in the northeastern part of the area. The results obtained using Slope methods indicate two depth sources in the area. On the average the deeper magnetic sources range from 2.0 to 4.99 km, while the shallower magnetic sources range from 0.4 to 1.99 km. Deeper magnetic sources probably depict depths to Precambrian Basement, whereas shallower sources probably depict depths to igneous intrusives and/or magnetized bodies within the sedimentary covers. Hydrocarbon exploration is not recommended since the area has low thickness of sediments on the average All these deductions were reached at after due consideration to both qualitative and quantitative interpretations supported by geological information of the area.

Archives of Applied Science Research, 2011

An aeromagnetic study of the Maiduguri-Dikwa depression in northeastern Nigeria has been carried ... more An aeromagnetic study of the Maiduguri-Dikwa depression in northeastern Nigeria has been carried out to establish its main shallow crustal structural features. The area is intensely fractured with major fractures trending in NE-SW direction. Spectral analysis and 2.0 D modeling of four profiles selected from the residual anomaly map provide depths to basement of 2.82, 3.41, 2.41 and 2.56 km. These depths constrain the magnetic models along the profiles, which indicate that the sedimentary infill is of variable thickness. Thus, we have three subbasins along the Maiduguri-Dikwa depression: Maiduguri, Mafa-Bama, and Dikwa subbasins. These sub-basins are associated with the extensional tectonics that affected the region from the Benue Trough to the Chad Basin. The Mafa-Bama sub-basin is the deepest one. The sedimentary infill is probably dominated with sandy clayey alluvial deposits, sandstones and shales. Depths to basement were constrained with by spectral analysis results.

Journal of African Earth Sciences, Mar 1, 2018

The Anambra basin constitutes the southeastern lower portion of the Benue Trough, which is a larg... more The Anambra basin constitutes the southeastern lower portion of the Benue Trough, which is a large structural depression that is divided into lower, middle and upper parts; and is one of the least studied inland sedimentary basins in Nigeria. Sequence stratigraphic interpretation had been carried out in parts of the Anambra Basin using data from three wells (Alo-1 Igbariam-1 and Ajire-1). Geophysical well logs and biostratigraphic data were integrated in order to identify key bounding surfaces, subdivide the sediment packages, correlate sand continuity and interpret the environment of deposition in the fields. Biostratigraphic interpretation, using foraminifera and plankton population and diversity, reveals five maximum flooding surfaces (MFS) in the fields. Five sequence boundaries (SB) were also identified using the well log analysis. Four 3 rd order genetic sequences bounded by maximum flooding surfaces (MFS-1 to MFS-6) were identified in the areas; four complete sequences and one incomplete sequence were identified in both Alo-1 and Igbariam-1 wells while Ajire-1 has an no complete sequence. The identified system tracts delineated comprises Lowstand Systems Tracts (progradational to aggradational to retrogradational packages), Transgressive Systems Tracts (retrogradational packages) and Highstand Systems Tracts (aggradational to progradational packages) in each well. The sand continuity across the fields reveal sands S1 to S5 where S1 is present in Ajire-1 well and Igbariam-1 well but not in Alo-1 well. The sands S4 to S5 run across the three fields at different depths. The formations penetrated by the wells starting from the base are; Nkporo Formation (Campanian), Mamu Formation (Late Campanian to Early Maastrichtian), Ajali Sandstone (Maastrichtian), Nsukka Formation (Late Maastrichtian to Early Palaeocene), Imo Formation (Palaeocene) and Nanka Sand (Eocene). The environments of deposition revealed are from coastal to bathyal. The sands of lowstand system tract and highstand system tract found in Ajali, Nsukka, Nkporo and Imo (Ebenebe Sandstone) Formations show good continuity and as such good reservoir qualities while the shales of the transgressive system tracts which includes the Imo Formation, Mamu, and Nkporo Formations where most of the maximum flooding surfaces were delineated, can serve as seals to the numerous reservoir units. Combinations of the reservoir sands of the lowstand system tract and highstand system tract and the shale units of the transgressive system tract can form good stratigraphic traps for hydrocarbon and hence should be hydrocarbon exploration targets.

Advances in Applied Science Research, 2012

A detailed interpretation of the aeromagnetic data has been carried out over parts of Upper Benue... more A detailed interpretation of the aeromagnetic data has been carried out over parts of Upper Benue Trough and Southern Chad Basin, Nigeria. The magnetic properties of rock were used to determine the depth to magnetic basement, model prominent magnetic anomaly, determine the basement topography and also determine various temperatures at depth in the study area. Two depth source models were interpreted using Discrete Fourier Transform method. Depth to the deeper magnetic sources ranges from 1.5 to 2.5 km, representing the sedimentary cover in the study area. The depth to the shallower magnetic source model which ranges from 0.5-1.4 km, represents intrusive bodies within the area. Based on the sedimentary thickness of 1.5 - 2.5 km and the temperature at depth of 81-1150C, the possibility of hydrocarbon generation towards the northeastern part of the study area is feasible.

International journal of advanced geosciences, Jan 12, 2016

Surface geo-electrical survey using vertical electrical sounding (VES) method has been carried ou... more Surface geo-electrical survey using vertical electrical sounding (VES) method has been carried out in Onitsha and environs in southwestern part of Anambra state in order to determine the aquifer characteristics and groundwater potential of the area. Eleven vertical electrical soundings were carried out within the area of study using schlumberger array configuration. The interpretation of the vertical electrical sounding (VES) data revealed three to five geoelectric units with depth to the aquiferous layers ranging from 21 to 78m and resistivity of the saturated layers varying between 20 and 5600 ohm-m. Aquifer characteristics such as transmissivity and hydraulic conductivity calculated from interpretated VES result ranged from 2.55m2/day to 29.01m2/day and 0.03m/day to 1.37m/day respectively. This result shows that the water saturated sandstone units of the study area is hydrological good and capable of producing optimum groundwater yield. Furthermore, borehole could be drilled at depth between 40 and 110m in the area for sustainable water supply and hydrochemical study carried out to determine the water quality for domestics and municipal purposes.

The hydrocarbon potentials of parts of the Nigerian sector of the Chad Basin have been re-evaluat... more The hydrocarbon potentials of parts of the Nigerian sector of the Chad Basin have been re-evaluated from the interpretation of aeromagnetic anomalies. Nine aeromagnetic maps located between latitudes 11 o 00 min - 12 o 30 min N and longitudes 12 o 30 min - 14 o 00 min E were assembled and analyzed to determine the structural pattern and the sedimentary thickness variations within the basin. The qualitative interpretation indicates that the area is intensely fractured with major faults trending in a NE-SW direction. The aeromagnetic data were subjected to Fourier analysis and results show two depth sources in the study area; the shallower sources have a average value of 1.8 km while the deeper ones have an average value of 4.3 km. The sedimentary thickness of the area ranges from 1.0 to 5.8 km. Based on the computed sedimentary thicknesses and the temperature at depth (125-228 o C), some parts of the study area have been demarcated for detail hydrocarbon exploration.

International Conference and Exhibition, Barcelona, Spain, 3-6 April 2016, Apr 3, 2016

Environmental Earth Sciences

Global Journal of Geological Sciences

The Asu River Group Shale in the Oshiri area was evaluated using ground magnetic and geoelectrica... more The Asu River Group Shale in the Oshiri area was evaluated using ground magnetic and geoelectrical methods within existing mine. Some exploration programs in the area have resulted to failure due to the fact that project managers have not fully understood the use and importance of geophysics in enhancing the search for mineral deposits. The aim of the study was to delineate the sulphide deposits using ground magnetics and geoelectrical methods. Result of the ground magnetic survey delineated some shallow tectonic structures like fractures and faults which are capable of hosting metallic sulphide deposits. The residual magnetic intensity of the study area indicates very low magnetic field intensities around the central and southern portions of the study area. These low values indicate absence of magnetite in the near surface materials as suggested by previous studies in the area, but could be referred to as zones with shallow tectonic structures which could be faults and/or fractures...

A combination of the IEC, AVI, and GOD pollution indices were used to assess the vulnerability of... more A combination of the IEC, AVI, and GOD pollution indices were used to assess the vulnerability of the fractured rock aquifer in the Abakaliki area to pollution from anthropogenic sources. The topsoil ranges from laterite to silt to silty-clay, according to the results of the vertical electrical sounding (VES). The geoelectric sections have varying numbers of layers (1–6 layers) with their resistivity ranges as 29.16–3,949.30 Ω, 4.98–1,630.70 Ωm, 0.35–3,767.20 Ωm,1.76–7926.30 Ωm, and 1.11–3,060.20 Ωm respectively. These have been grouped into four main lithologic units namely the topsoil, indurated/baked shale, fractured shale/sandstone (the aquiferous unit), and the consolidated sandstone units. The thickness of the vadose zone is generally thin (< 18 m), while their hydraulic conductivity is relatively high (0.20–16.11 m/day) for argillaceous rocks. The IEC values (0.003–0.850 S) suggest a weak to fair protective capacity for the vadose zone. The result of the HR (1.01–55.49) in...

Archives of Applied Science Research, 2015

A study of the character and dispersion patterns of groundroll was undertaken in Western Niger De... more A study of the character and dispersion patterns of groundroll was undertaken in Western Niger Delta in order to provide much needed information and solution for its suppression during seismic surveys. The quantitative analysis was carried out on raw monitor seismic records. The results revealed the occurrence of groundroll with predominant phase velocities of 500-1020 ms-1 (mean of 780 ms-1), frequency content of 4.0-9.0Hz (mean of 6.1Hz), wavelength of 61-240m (mean of 122m) and group mean velocity of 787 ms-1, with average standard deviation of 158 ms-1. The uphole data acquired was analyzed through direct or analytical determination of weathering velocities and thicknesses. The results shows that weathering and sub weathering velocities vary between 510 - 1012ms-1 with average value of 770ms-1 and 1368- 2474ms-1 with an average value of 1734ms-1 respectively. The determined thicknesses of the weathering layer ranges from 3.8 to 52.8m with an average value of 19.4m. The result sh...

Bulletin Of The Mineral Research and Exploration, 2021

The water sources in parts of the River Mamu sub-Basin, southeastern Nigeria were evaluated for d... more The water sources in parts of the River Mamu sub-Basin, southeastern Nigeria were evaluated for domestic and agricultural purposes using hydrogeology and water quality. Thirty water samples from both surface water and groundwater were analysed for hydrochemical and biological parameters. The average depth to aquifers and their thicknesses are 109.9m and 11.8m respectively. The concentration of the major ions, TDS and EC are within the DSÖ permissible guidelines for drinking water. Heavy metals concentration ranges in mg/L for Cd 2+ (0-0.06), Cr 3+ (0-0.19), Hg 2+ (0-1.0), As 3+ (0-0.14) and total Fe (0-2.4) which in some of the samples exceed the permissible guideline values. The fecal coliform range in 100ml/L of samples (0-36) exceeds the guideline values in some of the samples. The water is Ca-Mg-Cl-SO 4 type with the dominant ions as Ca 2+ and SO 4 2for both groundwater and surface water. The dominant geochemical processes are rock-water interaction in the groundwater, which is a major contributor of dissolved ions and precipitation in the surface water. The WQI (17.84-301.99) connotes some samples as very poor quality for domestic purposes. Irrigation indices depict most of the water as good to excellent for agriculture.

Bulletin Of The Mineral Research and Exploration, 2020

Thermomagnetic properties and geothermal energy potential in parts of Bida Basin, Nigeria have be... more Thermomagnetic properties and geothermal energy potential in parts of Bida Basin, Nigeria have been evaluated using spectral analysis of integrated nine aeromagnetic data. The study area covering 27.225 km 2 of aeromagnetic data was examined and construed in order to delineate the thermal properties of the country-rock in the area. The result of the visual inception of the residual map reveals that the area comprises an extremely irregular pattern of magnetic intensities that range from 220 to 240 nT. Two structural features of folding evidence were also delineated in the area namely; uplift and depression. The result of the lineament structures from the shaded relief map and Rose diagram depicts NE-SW as the major trend with the minor trend is NW-SE. Two depths to magnetic sources were distinguished in the area: the shallower bodies which vary from 1.27 to 1.96 km and the deeper bodies that vary from 2.01 to 4.27 km. The result also shows an average depth to the centroid as 12.97 km in the area. The thermomagnetic properties analysis show average values of 23.12 km Curie isotherm, 25.27 °C/km geothermal gradients and 63.17 mWm 2 heat flow in the area. The study concludes that the study area possesses good potential quality for geothermal energy generation and exploration.

Bulletin Of The Mineral Research and Exploration, 2020

This study examines the impact of solid waste on groundwater quality around three municipal dumps... more This study examines the impact of solid waste on groundwater quality around three municipal dumpsites in AkwaIbom State, Nigeria using resistivity and hydrochemical data. Thirty vertical electrical soundings and ten electrical resistivity tomography data were acquired across the area using Schlumberger array. The resistivity data which were analyzed with the aid of IPI2WIN software formed the input data for estimating and modeling leachate parameters. Twelve groundwater samples collected around the area were analyzed for physico-chemical parameters using Atomic Absorption Spectrometer (AAS). The leachate parameters computed from resistivity interpretation across the area show thickness (2 to 56 m); hydraulic conductivity (6.19 to 24.7 m/day); transmissivity (96.63 to 1351.18 m 2 /day) and erodibility (104.36 to 2948.94 m/day). The hydrochemical analyses reveal elevated values of Total Dissolved Solids, Cadmium and high electrical conductivity within the area. The leachate migration paths trend predominantly in NW-SE and NE-SW directions at Uyo and Oron, respectively. The hydrogeological risk models reveal that the static water level crisscrosses the leachate at 35 m in Oron, while Uyo area has 25 m gap between the leachate and the static water levels. The study concludes that Oron dumpsites really contaminated the groundwater quality and makes it unfit for the dwellers.

SEG Technical Program Expanded Abstracts 2017, 2017

Journal of Natural Sciences Research, 2015

One dimensional spectral analysis was applied to aeromagnetic data in order to determine the sedi... more One dimensional spectral analysis was applied to aeromagnetic data in order to determine the sedimentary thickness variations, depths to the Curie-temperature isotherm and heat flow measurements within the eastern part of the Nigerian Chad Basin. Two depths sources were interpreted in the area namely; the shallower sources have a mean value of 2.21 km while the deeper ones have an average value of 14.07 km. The result of the analysis shows that depths to the centriod and magnetic bodies (sedimentary thicknesses) range from 11.55 to 18.32 km and 1.65 to 5.12 km respectively. The depth to the Curie temperature isotherm in the area varies between 21.45 km at Mafa-Bama area and 31.52 km at Maiduguri-Gwoza area below sea level. The result also shows that the Curie temperature isotherm within the basin is not a horizontal level surface, but is undulating, and the geothermal gradients associated with it range between 17.45 and 25.64 o C/km while the corresponding mantle heat flow is about ...

Journal of Petroleum Exploration and Production Technology

In geophysical data interpretation, matching the vertical velocity direction from seismic data wi... more In geophysical data interpretation, matching the vertical velocity direction from seismic data with borehole-derived velocities is a challenging task because seismic-derived velocities are faster than borehole recorded velocities. This geophysical phenomenon is caused by velocity anisotropy. In this study, we used an empirical approach to estimate the degree of velocity anisotropy in the study area. The results showed that the delta anisotropy in sandstone beds varies from − 2.5% to 7.2% while most of them concentrate between 3.2% and 6.1%. The epsilon ranges between -6.4% and 9.3% while many of them concentrate between 3.2% and 7.2%. The gamma varies from − 6.3% to 7.3% while most of them concentrate between 1.2% and 5%. At shale beds, delta anisotropy varies from − 11.2% to 11.1% but most of them concentrate between 4.3% and 10.5%. The epsilon varies from − 7.2% to 14.5% while most of them concentrate between 4.5% and 10.5%. The gamma varies from 6.4% to 8.2% while majority of the...

Pure and Applied Geophysics, Jan 31, 2012

ABSTRACT Fractures are deformations in rocks with discontinuity. They are important in a number o... more ABSTRACT Fractures are deformations in rocks with discontinuity. They are important in a number of ways. Their presence significantly influences the strength and engineering properties as well as the hydraulic characteristics of rocks. Fractures may extend to the surface where they are observed and studied at outcrops. On the other hand, they may terminate in the subsurface or may be covered by overburden which makes them impossible to be studied and characterized at the ground surface. There has been an increasing interest in the location and characterization of fractures by earth scientists, engineers and other scientists, both at the surface and the subsurface. However, the unavailability or inaccessibility of good outcrops makes it imperative to develop methods and tools for studying fractures in the subsurface. Geophysical methods such as the resistivity methods have been very useful in this regard. The Azimuthal Square Array Resistivity Survey was used in this project to locate and characterize subsurface fractures in the crystalline rocks at Igarra. Results from the analysis and interpretation of the field data showed that the dominant fracture strike orientation is in the NNW–SSE direction. This compares well with the results of surface geologic mapping data which gave the general fracture strike orientation as N–S; however, the major large and extensive fractures are striking NNW–SSE. This information is very useful in modeling groundwater flow and contaminant transport; planning proper waste management programs as well as the Environmental Impact Assessment analysis for the study area. This study once more illustrates the satisfactory use of non-invasive geophysical methods in characterizing fractures in the subsurface especially where quality outcrops are not available or inaccessible.

Research journal of environmental and earth sciences, Aug 10, 2011

Total field aeromagnetic anomalies over Okigwe area have been evaluated in order to map lineament... more Total field aeromagnetic anomalies over Okigwe area have been evaluated in order to map lineaments and estimate the depths to basement (sedimentary thicknesses). Aeromagnetic contour map of Okigwe (Sheet 312) was acquired, digitized and analyzed. Regional-residual separation and Slope methods were applied. The magnetic lineament map shows major geologic lineaments trending in NE-SW direction with minor ones trending in NW-SE direction. The major trend is in conformity with the trend of the Benue Tough. Visual study of the map shows presence of igneous intrusives in the northeastern part of the area. The results obtained using Slope methods indicate two depth sources in the area. On the average the deeper magnetic sources range from 2.0 to 4.99 km, while the shallower magnetic sources range from 0.4 to 1.99 km. Deeper magnetic sources probably depict depths to Precambrian Basement, whereas shallower sources probably depict depths to igneous intrusives and/or magnetized bodies within the sedimentary covers. Hydrocarbon exploration is not recommended since the area has low thickness of sediments on the average All these deductions were reached at after due consideration to both qualitative and quantitative interpretations supported by geological information of the area.

Archives of Applied Science Research, 2011

An aeromagnetic study of the Maiduguri-Dikwa depression in northeastern Nigeria has been carried ... more An aeromagnetic study of the Maiduguri-Dikwa depression in northeastern Nigeria has been carried out to establish its main shallow crustal structural features. The area is intensely fractured with major fractures trending in NE-SW direction. Spectral analysis and 2.0 D modeling of four profiles selected from the residual anomaly map provide depths to basement of 2.82, 3.41, 2.41 and 2.56 km. These depths constrain the magnetic models along the profiles, which indicate that the sedimentary infill is of variable thickness. Thus, we have three subbasins along the Maiduguri-Dikwa depression: Maiduguri, Mafa-Bama, and Dikwa subbasins. These sub-basins are associated with the extensional tectonics that affected the region from the Benue Trough to the Chad Basin. The Mafa-Bama sub-basin is the deepest one. The sedimentary infill is probably dominated with sandy clayey alluvial deposits, sandstones and shales. Depths to basement were constrained with by spectral analysis results.

Journal of African Earth Sciences, Mar 1, 2018

The Anambra basin constitutes the southeastern lower portion of the Benue Trough, which is a larg... more The Anambra basin constitutes the southeastern lower portion of the Benue Trough, which is a large structural depression that is divided into lower, middle and upper parts; and is one of the least studied inland sedimentary basins in Nigeria. Sequence stratigraphic interpretation had been carried out in parts of the Anambra Basin using data from three wells (Alo-1 Igbariam-1 and Ajire-1). Geophysical well logs and biostratigraphic data were integrated in order to identify key bounding surfaces, subdivide the sediment packages, correlate sand continuity and interpret the environment of deposition in the fields. Biostratigraphic interpretation, using foraminifera and plankton population and diversity, reveals five maximum flooding surfaces (MFS) in the fields. Five sequence boundaries (SB) were also identified using the well log analysis. Four 3 rd order genetic sequences bounded by maximum flooding surfaces (MFS-1 to MFS-6) were identified in the areas; four complete sequences and one incomplete sequence were identified in both Alo-1 and Igbariam-1 wells while Ajire-1 has an no complete sequence. The identified system tracts delineated comprises Lowstand Systems Tracts (progradational to aggradational to retrogradational packages), Transgressive Systems Tracts (retrogradational packages) and Highstand Systems Tracts (aggradational to progradational packages) in each well. The sand continuity across the fields reveal sands S1 to S5 where S1 is present in Ajire-1 well and Igbariam-1 well but not in Alo-1 well. The sands S4 to S5 run across the three fields at different depths. The formations penetrated by the wells starting from the base are; Nkporo Formation (Campanian), Mamu Formation (Late Campanian to Early Maastrichtian), Ajali Sandstone (Maastrichtian), Nsukka Formation (Late Maastrichtian to Early Palaeocene), Imo Formation (Palaeocene) and Nanka Sand (Eocene). The environments of deposition revealed are from coastal to bathyal. The sands of lowstand system tract and highstand system tract found in Ajali, Nsukka, Nkporo and Imo (Ebenebe Sandstone) Formations show good continuity and as such good reservoir qualities while the shales of the transgressive system tracts which includes the Imo Formation, Mamu, and Nkporo Formations where most of the maximum flooding surfaces were delineated, can serve as seals to the numerous reservoir units. Combinations of the reservoir sands of the lowstand system tract and highstand system tract and the shale units of the transgressive system tract can form good stratigraphic traps for hydrocarbon and hence should be hydrocarbon exploration targets.

Advances in Applied Science Research, 2012

A detailed interpretation of the aeromagnetic data has been carried out over parts of Upper Benue... more A detailed interpretation of the aeromagnetic data has been carried out over parts of Upper Benue Trough and Southern Chad Basin, Nigeria. The magnetic properties of rock were used to determine the depth to magnetic basement, model prominent magnetic anomaly, determine the basement topography and also determine various temperatures at depth in the study area. Two depth source models were interpreted using Discrete Fourier Transform method. Depth to the deeper magnetic sources ranges from 1.5 to 2.5 km, representing the sedimentary cover in the study area. The depth to the shallower magnetic source model which ranges from 0.5-1.4 km, represents intrusive bodies within the area. Based on the sedimentary thickness of 1.5 - 2.5 km and the temperature at depth of 81-1150C, the possibility of hydrocarbon generation towards the northeastern part of the study area is feasible.

International journal of advanced geosciences, Jan 12, 2016

Surface geo-electrical survey using vertical electrical sounding (VES) method has been carried ou... more Surface geo-electrical survey using vertical electrical sounding (VES) method has been carried out in Onitsha and environs in southwestern part of Anambra state in order to determine the aquifer characteristics and groundwater potential of the area. Eleven vertical electrical soundings were carried out within the area of study using schlumberger array configuration. The interpretation of the vertical electrical sounding (VES) data revealed three to five geoelectric units with depth to the aquiferous layers ranging from 21 to 78m and resistivity of the saturated layers varying between 20 and 5600 ohm-m. Aquifer characteristics such as transmissivity and hydraulic conductivity calculated from interpretated VES result ranged from 2.55m2/day to 29.01m2/day and 0.03m/day to 1.37m/day respectively. This result shows that the water saturated sandstone units of the study area is hydrological good and capable of producing optimum groundwater yield. Furthermore, borehole could be drilled at depth between 40 and 110m in the area for sustainable water supply and hydrochemical study carried out to determine the water quality for domestics and municipal purposes.

The hydrocarbon potentials of parts of the Nigerian sector of the Chad Basin have been re-evaluat... more The hydrocarbon potentials of parts of the Nigerian sector of the Chad Basin have been re-evaluated from the interpretation of aeromagnetic anomalies. Nine aeromagnetic maps located between latitudes 11 o 00 min - 12 o 30 min N and longitudes 12 o 30 min - 14 o 00 min E were assembled and analyzed to determine the structural pattern and the sedimentary thickness variations within the basin. The qualitative interpretation indicates that the area is intensely fractured with major faults trending in a NE-SW direction. The aeromagnetic data were subjected to Fourier analysis and results show two depth sources in the study area; the shallower sources have a average value of 1.8 km while the deeper ones have an average value of 4.3 km. The sedimentary thickness of the area ranges from 1.0 to 5.8 km. Based on the computed sedimentary thicknesses and the temperature at depth (125-228 o C), some parts of the study area have been demarcated for detail hydrocarbon exploration.

International Conference and Exhibition, Barcelona, Spain, 3-6 April 2016, Apr 3, 2016

Environmental Earth Sciences

Global Journal of Geological Sciences

The Asu River Group Shale in the Oshiri area was evaluated using ground magnetic and geoelectrica... more The Asu River Group Shale in the Oshiri area was evaluated using ground magnetic and geoelectrical methods within existing mine. Some exploration programs in the area have resulted to failure due to the fact that project managers have not fully understood the use and importance of geophysics in enhancing the search for mineral deposits. The aim of the study was to delineate the sulphide deposits using ground magnetics and geoelectrical methods. Result of the ground magnetic survey delineated some shallow tectonic structures like fractures and faults which are capable of hosting metallic sulphide deposits. The residual magnetic intensity of the study area indicates very low magnetic field intensities around the central and southern portions of the study area. These low values indicate absence of magnetite in the near surface materials as suggested by previous studies in the area, but could be referred to as zones with shallow tectonic structures which could be faults and/or fractures...

A combination of the IEC, AVI, and GOD pollution indices were used to assess the vulnerability of... more A combination of the IEC, AVI, and GOD pollution indices were used to assess the vulnerability of the fractured rock aquifer in the Abakaliki area to pollution from anthropogenic sources. The topsoil ranges from laterite to silt to silty-clay, according to the results of the vertical electrical sounding (VES). The geoelectric sections have varying numbers of layers (1–6 layers) with their resistivity ranges as 29.16–3,949.30 Ω, 4.98–1,630.70 Ωm, 0.35–3,767.20 Ωm,1.76–7926.30 Ωm, and 1.11–3,060.20 Ωm respectively. These have been grouped into four main lithologic units namely the topsoil, indurated/baked shale, fractured shale/sandstone (the aquiferous unit), and the consolidated sandstone units. The thickness of the vadose zone is generally thin (< 18 m), while their hydraulic conductivity is relatively high (0.20–16.11 m/day) for argillaceous rocks. The IEC values (0.003–0.850 S) suggest a weak to fair protective capacity for the vadose zone. The result of the HR (1.01–55.49) in...

Archives of Applied Science Research, 2015

A study of the character and dispersion patterns of groundroll was undertaken in Western Niger De... more A study of the character and dispersion patterns of groundroll was undertaken in Western Niger Delta in order to provide much needed information and solution for its suppression during seismic surveys. The quantitative analysis was carried out on raw monitor seismic records. The results revealed the occurrence of groundroll with predominant phase velocities of 500-1020 ms-1 (mean of 780 ms-1), frequency content of 4.0-9.0Hz (mean of 6.1Hz), wavelength of 61-240m (mean of 122m) and group mean velocity of 787 ms-1, with average standard deviation of 158 ms-1. The uphole data acquired was analyzed through direct or analytical determination of weathering velocities and thicknesses. The results shows that weathering and sub weathering velocities vary between 510 - 1012ms-1 with average value of 770ms-1 and 1368- 2474ms-1 with an average value of 1734ms-1 respectively. The determined thicknesses of the weathering layer ranges from 3.8 to 52.8m with an average value of 19.4m. The result sh...

Bulletin Of The Mineral Research and Exploration, 2021

The water sources in parts of the River Mamu sub-Basin, southeastern Nigeria were evaluated for d... more The water sources in parts of the River Mamu sub-Basin, southeastern Nigeria were evaluated for domestic and agricultural purposes using hydrogeology and water quality. Thirty water samples from both surface water and groundwater were analysed for hydrochemical and biological parameters. The average depth to aquifers and their thicknesses are 109.9m and 11.8m respectively. The concentration of the major ions, TDS and EC are within the DSÖ permissible guidelines for drinking water. Heavy metals concentration ranges in mg/L for Cd 2+ (0-0.06), Cr 3+ (0-0.19), Hg 2+ (0-1.0), As 3+ (0-0.14) and total Fe (0-2.4) which in some of the samples exceed the permissible guideline values. The fecal coliform range in 100ml/L of samples (0-36) exceeds the guideline values in some of the samples. The water is Ca-Mg-Cl-SO 4 type with the dominant ions as Ca 2+ and SO 4 2for both groundwater and surface water. The dominant geochemical processes are rock-water interaction in the groundwater, which is a major contributor of dissolved ions and precipitation in the surface water. The WQI (17.84-301.99) connotes some samples as very poor quality for domestic purposes. Irrigation indices depict most of the water as good to excellent for agriculture.

Bulletin Of The Mineral Research and Exploration, 2020

Thermomagnetic properties and geothermal energy potential in parts of Bida Basin, Nigeria have be... more Thermomagnetic properties and geothermal energy potential in parts of Bida Basin, Nigeria have been evaluated using spectral analysis of integrated nine aeromagnetic data. The study area covering 27.225 km 2 of aeromagnetic data was examined and construed in order to delineate the thermal properties of the country-rock in the area. The result of the visual inception of the residual map reveals that the area comprises an extremely irregular pattern of magnetic intensities that range from 220 to 240 nT. Two structural features of folding evidence were also delineated in the area namely; uplift and depression. The result of the lineament structures from the shaded relief map and Rose diagram depicts NE-SW as the major trend with the minor trend is NW-SE. Two depths to magnetic sources were distinguished in the area: the shallower bodies which vary from 1.27 to 1.96 km and the deeper bodies that vary from 2.01 to 4.27 km. The result also shows an average depth to the centroid as 12.97 km in the area. The thermomagnetic properties analysis show average values of 23.12 km Curie isotherm, 25.27 °C/km geothermal gradients and 63.17 mWm 2 heat flow in the area. The study concludes that the study area possesses good potential quality for geothermal energy generation and exploration.

Bulletin Of The Mineral Research and Exploration, 2020

This study examines the impact of solid waste on groundwater quality around three municipal dumps... more This study examines the impact of solid waste on groundwater quality around three municipal dumpsites in AkwaIbom State, Nigeria using resistivity and hydrochemical data. Thirty vertical electrical soundings and ten electrical resistivity tomography data were acquired across the area using Schlumberger array. The resistivity data which were analyzed with the aid of IPI2WIN software formed the input data for estimating and modeling leachate parameters. Twelve groundwater samples collected around the area were analyzed for physico-chemical parameters using Atomic Absorption Spectrometer (AAS). The leachate parameters computed from resistivity interpretation across the area show thickness (2 to 56 m); hydraulic conductivity (6.19 to 24.7 m/day); transmissivity (96.63 to 1351.18 m 2 /day) and erodibility (104.36 to 2948.94 m/day). The hydrochemical analyses reveal elevated values of Total Dissolved Solids, Cadmium and high electrical conductivity within the area. The leachate migration paths trend predominantly in NW-SE and NE-SW directions at Uyo and Oron, respectively. The hydrogeological risk models reveal that the static water level crisscrosses the leachate at 35 m in Oron, while Uyo area has 25 m gap between the leachate and the static water levels. The study concludes that Oron dumpsites really contaminated the groundwater quality and makes it unfit for the dwellers.

SEG Technical Program Expanded Abstracts 2017, 2017

Journal of Natural Sciences Research, 2015

One dimensional spectral analysis was applied to aeromagnetic data in order to determine the sedi... more One dimensional spectral analysis was applied to aeromagnetic data in order to determine the sedimentary thickness variations, depths to the Curie-temperature isotherm and heat flow measurements within the eastern part of the Nigerian Chad Basin. Two depths sources were interpreted in the area namely; the shallower sources have a mean value of 2.21 km while the deeper ones have an average value of 14.07 km. The result of the analysis shows that depths to the centriod and magnetic bodies (sedimentary thicknesses) range from 11.55 to 18.32 km and 1.65 to 5.12 km respectively. The depth to the Curie temperature isotherm in the area varies between 21.45 km at Mafa-Bama area and 31.52 km at Maiduguri-Gwoza area below sea level. The result also shows that the Curie temperature isotherm within the basin is not a horizontal level surface, but is undulating, and the geothermal gradients associated with it range between 17.45 and 25.64 o C/km while the corresponding mantle heat flow is about ...

Journal of Petroleum Exploration and Production Technology

In geophysical data interpretation, matching the vertical velocity direction from seismic data wi... more In geophysical data interpretation, matching the vertical velocity direction from seismic data with borehole-derived velocities is a challenging task because seismic-derived velocities are faster than borehole recorded velocities. This geophysical phenomenon is caused by velocity anisotropy. In this study, we used an empirical approach to estimate the degree of velocity anisotropy in the study area. The results showed that the delta anisotropy in sandstone beds varies from − 2.5% to 7.2% while most of them concentrate between 3.2% and 6.1%. The epsilon ranges between -6.4% and 9.3% while many of them concentrate between 3.2% and 7.2%. The gamma varies from − 6.3% to 7.3% while most of them concentrate between 1.2% and 5%. At shale beds, delta anisotropy varies from − 11.2% to 11.1% but most of them concentrate between 4.3% and 10.5%. The epsilon varies from − 7.2% to 14.5% while most of them concentrate between 4.5% and 10.5%. The gamma varies from 6.4% to 8.2% while majority of the...