http://repository.fuoye.edu.ng:80/handle/123456789/796 Thu, 16 Apr 2026 07:21:29 GMT 2026-04-16T07:21:29Z http://repository.fuoye.edu.ng:80/handle/123456789/1242 Title: Geochemistry and Quality Characterization of Effon Psammite Ridge Spring Water, Southwestern Nigeria Authors: Nwankwoala, Hycienth O; Nwaogu, C; Bolaji, Taiwo A; Uzoegbu, M. U; Abrakasa, S; Amadi, A. N Abstract: This study evaluates the geochemistry and quality characterization in the Effon Psammite Spring, Southwestern Nigeria. Fifteen (15) water samples were collected from the study area at regular intervals and samples were analyzed in order to determine their quality characteristics. Except for pH values that is mildly acidic to slightly alkaline in some locations, the physico-chemical properties are below the WHO recommended standards for drinking water. The low values of the conductivity are mainly attributed to geochemical processes prevailing in the area. The mean concentration of the cations follows the order: Na+ >Ca2+ >K+ >Mg2+ while for anions, HCO3- >Cl- > PO3- >SO42- >NO3-. The water is mildly acidic to alkaline due to dissociation of bicarbonate with the following water types: Na-SO4-Cl, NaHCO 3, Ca-Na-SO4 and Ca-Mg-HCO3-SO4 which are a reflction of geology and climate of the area. The mildly acidic to alkaline indices revealed that the spring water has undergone ion exchange between Na+K ions in the water with Ca and Mg of soil during the residence time of the water. The springs are being recharged from recent precipitation that has low water-rock interactions and low residence time within the aquiferous zones. The hydrochemical trend signifis low mineralized water with low water-rock interactions and residence time. Based on these water types and the presence of Na+, the concentrations of cations are geogenic in origin and might have come from the interaction of water and the rock or introduced from weathering of rocks into the spring water. It is recommended that effective development of springs should involve thorough examination of their seasonal discharges, including during the summer. In case water supply exceeds use, the surplus waters may be stored for future use in horticulture and to irrigate crop land. Moreso since springs are yet to receive substantial attention, utmost care must be taken to protect the Effon Psammite spring from contamination. Thu, 01 Jan 2015 00:00:00 GMT http://repository.fuoye.edu.ng:80/handle/123456789/1242 2015-01-01T00:00:00Z http://repository.fuoye.edu.ng:80/handle/123456789/954 Title: Petroleum Source Rock Potential Assessment of the Oligocene - Miocene Ogwashi Asaba Formation, Southern Anambra Basin, Nigeria Authors: Akande, Samuel O.; ADEOYE, MOSES. O; Erdtmann, Bernd D. Abstract: The Oligocene - Miocene Ogwashi Asaba Formation of the Anambra Basin is the outcropping equivalent of the Agbada Formation in the Niger Delta, subsurface. Exposed rocks of this formation consist of interbedded successions of lignite, shale, claystone, siltstone, sandstone, and conglomerate facies of a paralic environment. The present study has investigated the petroleum potentials of the outcrop samples exposed at Azagba Ogwashi, Oba and Ihioma areas from the organic petrologic and geochemical viewpoints. Maceral analysis revealed that the Azagba Ogwashi lignites have an average composition of huminite : liptinite : inertinite (H: L : I) ratio of 60:31:9, 79:18:3 for the Oba lignites, and 71:21:8 for the Ihioma lignites. Maceral constituent ratio in the shales range from 72:22:6 in Azagba Ogwashi, 83:7:10 for Oba, and 69:30:1 in the Ihioma area. Total Organic Carbon (TOC) of the lignite samples range from 13.28 to 68.04wt% (mean = 46.56 wt%) for twenty samples whereas those of the shales range from 4.98 to 12.38wt% (mean = 8.52wt%) for thirteen samples. Petroleum source potential (S1 + S2) for the lignites range from 13.05 – 460.63 kg HC/t (mean = 133.59 kg HC/t) and HI range from 53 to 639 mgHC/gTOC (mean = 234.85 mgHC/gTOC). In the shale samples, S1 + S2 range from 1.25 – 35.19 kg HC/t (mean = 14.59 kg HC/t) and HI range from 17 to 260 mgHC/gTOC (mean = 129.52 mgHC/gTOC). The Tmax values range from 394°C - 421°C (mean = 411°C) in the lignites while those of the shales range from 384 to 426°C (mean = 411°C). The relatively high proportion of liptinite (Type II kerogen) in the lignite especially in Azagba Ogwashi suggests its potential for oil generation, while the predominance of huminite (Type III kerogen) in Oba and Ihioma suggest their potential for gas generation in the deeper section of the basin where the appropriate thermal maturity would have been attained. The source rock facies investigated have good to excellent organic matter content and can therefore be considered as potential petroleum source rocks which upon thermal maturity will generate oil and gas. This conclusion suggests that equivalent lithologic units in the Agbada formation are candidate petroleum source rocks in the subsurface Niger Delta. Description: The paper investigated the petroleum potentials of the outcrop rocks exposed at Azagba Ogwashi, Oba and Ihioma areas of Anambra Basin, from the organic petrologic and geochemical viewpoints. Thu, 01 Jan 2015 00:00:00 GMT http://repository.fuoye.edu.ng:80/handle/123456789/954 2015-01-01T00:00:00Z