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- ItemOpen AccessGEOPHYSICAL ASSESSMENT FOR CARBON DIOXIDE (CO2) SEQUESTRATION IN “IT” FIELD, NIGER DELTA, NIGERIA(Department Of Physics And Engineering Physics, Faculty Of Sciences, Obafemi Awolowo University Ile-Ife., 2022) ADENIKA Charles ItunuThis study established the fault framework of theThis study established the fault framework of the reservoir environment, identified suitable reservoirs, determined petrophysical parameters of the identified reservoirs, estimated the storage capacity of the reservoirs and determined the sealing efficiency within IT field Niger Delta, Nigeria. These were with a view to assessing the suitability and utilization of IT field for implementation of geological CO2 sequestration. High resolution aeromagnetic, 3D seismic and well log data were used. The magnetic data were gridded, reduced to equator and upward continued to produce residual magnetic intensity (RMI) map. Quantitative processes were applied on the RMI to estimate the sedimentary thickness and delineate lineaments on a regional scale. Hydrocarbon reservoirs were mapped and their petrophysical parameters computed from well log data. Fault and horizon mapping were carried out on the vertical seismic sections to produce structural maps. The structural maps and petrophysical parameters obtained were used to determine the storage capacities of the identified hydrocarbon reservoirs. The calculated volume of shale (Vshale) was used to generate fault models which were used to evaluate the sealing efficiency of the mapped faults. Compressional wave velocity (Vp) and shear wave velocity (Vs) obtained from identified reservoirs and shales (caprocks) were used to compute, model and analyze geomechanical parameters to deduce the sealing efficiency of the identified reservoirs and caprocks. The results showed that the sedimentary thickness ranged from 2.5 km to 21.5 km with a mean of 10 km. The basement structures delineated trended majorly in the NE-SW direction and were deep seated structures which may not influence the overburden. Three sand reservoirs; RES-1, RES-2 and RES-3, were identified and mapped across six wells (IT-01 to IT-06). Results of petrophysical analysis revealed gross thickness values of 145.25, 98.86 and 474.94 ft; porosity values of 0.29, 0.22 and 0.27; hydrocarbon saturation values of 0.29, 0.45 and 0.64; permeability values of 3890, 243.24 and 2401.95 mD; and Net-to-Gross values of 0.90, 0.36 and 0.69 for RES-1, RES-2 and RES-3 respectively. The storage capacity computed from the petrophysical and volumetric analyses, and storage efficiency factors for RES-1, RES-2 and RES-3 using DOE model (1% and 4%) revealed 49.42 Mtons and 197.77 Mtons; 16.00 Mtons and 64.02 Mtons, and 1.35 Gtons and 5.67 Gtons; respectively. According to Goodman’s model (10% and 15%), RES-1, RES-2 and RES-3 were estimated to have storage capacity of 494.30 Mtons and 741.45 Mtons; 160.00 Mtons and 240.07 Mtons, and 13.52 Gtons and 20.29 Gtons; respectively. RES-3 was adjudged the reservoir with the largest storage capacity. Fault seal analyses revealed that fault sealing percentages ranged from 20 – 60 %, indicating that the reservoirs are assisted by moderately sealing faults which are capable of sealing the reservoir for a longer period. Geomechanical analyses revealed that the identified reservoirs and caprocks are ductile and possess sufficient strength to withstand external pressure. The study concluded that IT field contain reservoirs which have moderate fault seal capacity, appreciably thick caprocks with very good storage capacity thereby indicating that the field is capable of hosting CO2 sequestration. xviii identified suitable reservoirs, determined petrophysical parameters of the identified reservoirs, estimated the storage capacity of the reservoirs and determined the sealing efficiency within IT field Niger Delta, Nigeria. These were with a view to assessing the suitability and utilization of IT field for implementation of geological CO2 sequestration. High resolution aeromagnetic, 3D seismic and well log data were used. The magnetic data were gridded, reduced to equator and upward continued to produce residual magnetic intensity (RMI) map. Quantitative processes were applied on the RMI to estimate the sedimentary thickness and delineate lineaments on a regional scale. Hydrocarbon reservoirs were mapped and their petrophysical parameters computed from well log data. Fault and horizon mapping were carried out on the vertical seismic sections to produce structural maps. The structural maps and petrophysical parameters obtained were used to determine the storage capacities of the identified hydrocarbon reservoirs. The calculated volume of shale (Vshale) was used to generate fault models which were used to evaluate the sealing efficiency of the mapped faults. Compressional wave velocity (Vp) and shear wave velocity (Vs) obtained from identified reservoirs and shales (caprocks) were used to compute, model and analyze geomechanical parameters to deduce the sealing efficiency of the identified reservoirs and caprocks. The results showed that the sedimentary thickness ranged from 2.5 km to 21.5 km with a mean of 10 km. The basement structures delineated trended majorly in the NE-SW direction and were deep seated structures which may not influence the overburden. Three sand reservoirs; RES-1, RES-2 and RES-3, were identified and mapped across six wells (IT-01 to IT-06). Results of petrophysical analysis revealed gross thickness values of 145.25, 98.86 and 474.94 ft; porosity values of 0.29, 0.22 and 0.27; hydrocarbon saturation values of 0.29, 0.45 and 0.64; permeability values of 3890, 243.24 and 2401.95 mD; and Net-to-Gross values of 0.90, 0.36 and 0.69 for RES-1, RES-2 and RES-3 respectively. The storage capacity computed from the petrophysical and volumetric analyses, and storage efficiency factors for RES-1, RES-2 and RES-3 using DOE model (1% and 4%) revealed 49.42 Mtons and 197.77 Mtons; 16.00 Mtons and 64.02 Mtons, and 1.35 Gtons and 5.67 Gtons; respectively. According to Goodman’s model (10% and 15%), RES-1, RES-2 and RES-3 were estimated to have storage capacity of 494.30 Mtons and 741.45 Mtons; 160.00 Mtons and 240.07 Mtons, and 13.52 Gtons and 20.29 Gtons; respectively. RES-3 was adjudged the reservoir with the largest storage capacity. Fault seal analyses revealed that fault sealing percentages ranged from 20 – 60 %, indicating that the reservoirs are assisted by moderately sealing faults which are capable of sealing the reservoir for a longer period. Geomechanical analyses revealed that the identified reservoirs and caprocks are ductile and possess sufficient strength to withstand external pressure. The study concluded that IT field contain reservoirs which have moderate fault seal capacity, appreciably thick caprocks with very good storage capacity thereby indicating that the field is capable of hosting CO2 sequestration.
- ItemOpen AccessChemical studies on the deterioration of palm oil(Department of Chemistry, Obafemi Awolowo University., 1983) OKIY, Dere AruboreThe work reported in this thesis is on the chemical changes which take place when palm oil is subjected to thermal deterioration and the effect on the nutritional value of leaf protein. The state of deteriorated palm oil on the nutritional value of leaf protein as determined by PER, BV, NPU and TD were examined; this was not worse than diets without the oil samples.
- ItemOpen AccessPurification and characterization of Arginase from the liver of land Tortoise.(Department of Biochemistry Obafemi Awolowo University, 2011) OKONJI Raphael EmuebieThe study of the Physicochemical, catalytic, structural and immunological characteristics of arginase from tortoise, a uricotelic organism was undertaken in order to provide information which would demonstrate the differences between the ureotelic and uricotelic arginases. In conclusion, tortoise liver arginase was similar to those of uricotelics in terms of kinetic and physicochemical properties. The physiological role of the enzyme in uricotelics involved the conversion of ornithine to proline and glutamate
- ItemOpen AccessPhysico-Chemical and trace element characteristics of vegetation, soil and water in Bituminous sands deposit area of Ondo state, Southwestern Nigeria.(Department of Chemistry, Faculty of Science, Obafemi Awolowo University, Ile-Ife., 2007) Adedbiyi, Festus MayowaVegetation, soil and water (ground and Surface water) in bituminous sands deposit area of Ondo state, Southwestern Nigeria were analyzed for the physic-chemical characteristics and trace element contents with a view to providing baseline data for these parameters in the various ecological components and a framework for establishing of relationships between the chemistry of mineral deposits and the soil, water and vegetation in the study.
- ItemOpen AccessThe Biology of the fish genus clarias in Opa reservoir, Obafemi Awolowo University(Department of Zoology, Faculty of Science, Obafemi Awolowo University., 1995) ABAYOMI, Olatokunbo SolomonA study on the identification , distribution, food and feeding habits, pattern of reproduction, and fecundity , age and growth and types of parasites affecting the fish genus clarias was carried out in Opa reservoir between 1989 and 1992.