Volume 2 Number 4 April 2016

Base Metal Mineralization in the Precambrian Rocks of Okemesi-Ijero Area, Southwestern Nigeria

Authors: Ayodele O.S. ; Madukwe Y. Henry ; Azeez M.A. ; Awokunmi E.E.
Pages: 57-67
The evaluation of base metals in the bedrocks of Okemesi / Ijero area, southwestern Nigeria has been carried out to assess their potentials, level of accumulation and enrichment. The methodology included systematic geological and geochemical mapping of the rocks using grid-controlled sampling method at a sampling density of one sample per 500m. Ten rock samples were collected at different locations of the study area. The results obtained showed that the major oxides such as SiO2, Al2O3, TiO2, Fe2O3, MnO, MgO, CaO, Na2O, K2O and P2O5 were detected in variable proportions. While SiO2 variedbetween 70.59% and 98.70%, Al2O3 ranged between 15.73% and 0.61%. There is abundanceof barium (Ba), silver (Ag) and gold (Au) with concentration values of 1.6-9.8, 1.24-7.1 and 0.05-10.00 ppm respectively. Base metals such as Cu, Zn, Pb, Bi and Cr enrichment factors and their geo-accumulation index indicates moderately significance to very high enrichment of Cu (10 – 70%) , Pb (20 – 40%) and Bi (10 – 40%). The geo-accumulation indices suggest geogenic concentration of the base metals in the host rocks rather than anthropogenic inputs. The PCA elements loaded Au, As, Ag, Pt and Os on the same factor and they are pathfinder elements of Gold. Correlation coefficients indicate strong positive correlations between the elements. This implies that they are strongly related and therefore of the same source, also suggesting geogenic sources.

Comparative Limnological Studies of Nnamdi Azikiwe University (Unizik) and Amansea Streams in Awka South L.G.A., Anambra State, Nigeria

Authors: Okoye Charles O.
Pages: 53-56
The limnological studies of Unizik and Amansea streams, Awka South Local Governments Area, Anambra State, Nigeria, were carried out using standard methods. The mean water temperature, dissolved oxygen content, transparency and pH were 26.330C, 2.75 mg/l, 49.10cm and 7.80 respectively, in Unizik Stream. For Amansea Stream, the values were 26.580C, 2.40mg/l, 35.87cm and 7.70, respectively. The mean BOD, Alkalinity, water depth and water current values recorded in Unizik stream were 16.00mg/l 119.70mg/l,58.25cm and 0.45m/s respectively, while in Amansea Stream the values were 11.50mg/l, 111.35mg/l, 59.43cm and 0.39/s respectively. The physicochemical parameters of the two streams vary spatially. Unizik and Amansea streams exhibited features that are typical of streams in tropical environment. The low dissolved oxygen content, high biochemical oxygen demand and low alkalinity values indicate that the water bodies are unsuitable to support aquatic life.