The Ajali Sandstone, western flank, Anambra Basin, was studied for textural characteristics and maturity of the sediments. Grain size analysis (51 samples), thin section and heavy mineral analysis (15 samples each) and XRF fusion for metallic oxides (15 samples) were analyzed. The textural parameters show that the Ajali Sandstone are medium sand, poorly to moderately sorted, coarse to strongly coarse skewed with mesokurtic to leptokurtic grains. The thin section analysis reveals grains that are sub-angular to sub-rounded (this typifies grains that have travelled fairly long distance to the deposition site), of moderate to well sorted grains, with both monocrystalline and polycrystalline quarts-grains type, with a modal composition of Q F and L . A mineralogical maturity 90.4, 2.3 2.9 index (MMI) of 17.04, SiO /Al O ratio of 180.24, and a ZTR index of 67.96% were obtained. The values for the 2 2 3 MMI and SiO /Al O indicates mineralogical matured sediments, the ZTR index shows a chemically immature 2 2 3 to sub-mature sandstone, and the modal composition values are consistent with a texturally and compositionally matured sands. The mineralogical maturity is indicative of high degree of chemical weathering of source area. Furthermore, the high quartz and silica content make the sandstone  prospective for glass and glassware production. Key words: Anambra Basin, Maturity, Mineralogical maturity index, Textural characteristics, Glass

The Ajali Sandstone, South-western, Anambra Basin, was studied for Rare Earth Elements (REEs), using a Phillips 45 channel Inductively Coupled Plasma (ICP) Emission Spectrometer. The standard deviation of the REEs (Dy, Er, Eu, Y, Yb, La and Nd) averages 3.5 mg/L, 0.34 mg/L, 0.32 mg/L, 3.93 mg/L, 1.96 mg/L, 4.02 mg/L and 2.24 mg/L respectively for each of the sampled locations. The REEs concentrations showed both positive and negative concentration anomalies. The enrichment or depletion of the REEs is generally attributed to their tendency to be incorporated into plagioclase preferentially over other minerals. The Ajali Formation is predominantly sand/sandstone, with clay occurring only as intercalations/thin beds of clay drapes with the increasing particle size of the sand grains, makes the rate of adsorption and distribution of REEs in the soil low, and explains the low values of REEs concentration. Soil organic matter (SOC) plays an important role in the adsorption and migration of REEs in the Ecosystems. The SOC is linearly associated with REEs Concentration as it increases with increasing content of SOC. The Ajali Sandstone studied falls in the vicinity of abandoned cropland to cropland in a lower/gentle slope region, correspondingly low in soil organic matter content and as such slow rate of distribution and migration of REEs concentrations in the Ajali Sandstone. The sesquioxides such as Fe oxides increases as REEs contents increases. The 0.46 mean value of Fe2O3 in the Sandstone of the area studied implies a low REEs adsorption rate and subsequently the very low REEs concentrations of the soils. The istribution of REEs within the Ajali Formation soils were grossly affected by the factors that influenced the adsorption and migration rate of the minerals during magmatic fractionation process, hence the low REEs concentration of the Sediments. Keywords`: Sansdstone, Anambra Basin, Rare Earth Elements, Magmatic fractionation

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Integrated wireline logs and lithostratigraphic techniques were employed to determine the lithological and petrophysical properties of wells A and B in E- field, onshore Niger Delta. The Reservoirs in both wells were analyzed using a minimum thickness or depth of penetration of 5.0m. For the two wells, Gas Water Contact (GWC), Gas Oil Contact (GOC), and Oil Water Contact (OWC) were found to be present at varying formation depths. GWC, GOC, and OWC at depth of 2967.50m, 3348m and 2286m respectively for well A and a GOC at depth 1715m for well B. The correlation of both wells reveals a gas reservoir, water reservoir, and a non-resistive, but highlyconductive zone at 2450m, 2500m, and 2150m depth respectively. The formation porosity (∅𝑫), total porosity (∅𝑻), effective porosity (∅𝑬) and resistivity values of well A ranges from (27.27 - 39.59) %, (1.3x10 –1 - 37.82) %, ( 1.638x10– 4 – 81. 38)%, (2.05 - 150)Ωm respectively. Conversely, well B measured (27.27 - 36.50) %, (2.25x10–2 - 93.0) %, (9.75x10– 4 - 32.79) % and (2 – 200) Ωm respectively. Hydrocarbon saturation (SHC) and Bulk volume of Hydrocarbon (BVH) for well A ranges from (73.27-95.10)% and (24.24 - 34. 58)% while that of well B ranges from (77.10 - 97. 90)% and (23.36 - 35.53)% for SHC and BVH respectively. The average ∅𝑻 and ∅𝑬 of 56.2% and 42.6% reveal excellent porosities in well A and reservoirs 2,3,4a and 11 in well B with average ∅𝑻and ∅𝑬 of 37.82% and 30.6% also show an excellent porosities. The result from the Petrophysical indices indicates pay zones at reservoirs 10a, 10b and 11 in well A andreservoir 11 in well B which are predominantly gas reserves. Keywords: Reservoirs, Onshore, Oil and Gas, Petrophysical properties, Niger Delta and Lithology

Global demand increase for rare metals deposits has re-enacted the search for economically viable deposits. Precambrian pegmatites occurring as near dykes and massive types were studied for Emure-Ekiti and Ijero-Ekiti respectively, with the aim of characterizing them geochemically and determining their possible economics values. A total of twelve samples comprising seven from Emure-Ekiti, three whole rock muscovite extract for Ijero-Ekiti were analysed for major and trace elements using X-ray fluorescence method. Thin sections prepared for the Emure-Ekiti pegmatites show that quartz, microcline are major mineral constituents. The geochemical results reveals that the Emure-Ekiti and the whole rock samples of Ijero-Ekiti are considerably siliceous, with an average value of 68.72% and 68.6% respectively, while the muscovites extracts average 48.86%. Mean values of major oxides for the Emure, Ijero[whole rock, muscovite] are as follows; Al2O3 - 20.42%, [13.74%, 35.15%]; Fe2O3 - 1.83%, [1.24%, 2.19%]; MgO - 0.013%, [0.029%, 1.04%]; CaO - 0.02%, [0.34%, 2.4%]; Na2O – 1.01%, [4.40%, 1.045%]; K2O – 3.17%, [2.77%, 11.07%]. Trace and rare-earth elements result shows that the Emure-Ekiti pegmatites is “barren” – depleted in rare metals Ta, Nb, Cs, Sn, Rb, etc, and compare favourably with Apomu, Ago-Iwoye and Ijebu-Ife barren pegmatites. On the other hand, two of the whole rock samples are mineralized – fairly enriched in rare metals Ta, Nb, Rb while the remaining sample and the muscovite extract are barren; as depicted by the Rb vs Rb plot and when compared to the other rare metal pegmatites across the world.