Abstract: The evaluation of environmental impact of artisanal gold mining was carried out in Luku, Minna, North Central Nigeria, to evaluate environmental hazards associated with artisanal gold mining through field work and Laboratory analyses. During the field work, observations of the whole mining site were made so as to evaluate the physical impact of mining and representative soil samples were randomly collected from the surface from mined and un-mined areas within the mining sites. The soil samples were analysed at the National Geo-science Research Laboratory (NGRL), of Nigerian Geological Survey Agency (NGSA), Kaduna for trace elements using X-Ray Fluorescence (XRF) method. The average concentration of these elements was compared with the published crustal average concentration of the elements in upper continental crust. Results of field observation reveal that mining activity resulted in lot of physical environmental impact such as land degradation, destruction of vegetation, erosion of soils and degrading water quality. Results from the laboratory analyses show that soils are contaminated with elements such as Pb (85.73 ppm), As (9.27 ppm), Cu (56.46 ppm), Zn (31 ppm), Ni (85.55 ppm), Mn (283.73 ppm), Cd (1.68 ppm), Co (10.91 ppm), Mo (0.91 ppm), Hg (0.27 ppm), Ag (0.73 ppm), and Zr (143.27 ppm). These elements in the soil get accumulated in plants and animals, and are passed on to human through the food chain. Also, these elements can find their way to surface and ground water making the water unsuitable for human consumption. It may cause slow growth rate in plants and respiratory problem, liver and kidney damage in man.

Abstract: In recent years there has been considerable breakthrough in acquisition of georeferenced qualitative data. These types of data have characteristics that distinguish them from quantitative datasets and therefore it is typically more challenging to discover knowledge from such spatio-qualitative data. SoftGIS is one of the most prominent attempts in in collecting such spatio-qualitative data that is capable of providing informative data with applications in different disciplines. This paper uses this dataset in a case of urban experience in Helsinki in order to propound a visual technique that can help with knowledge discovery process. The visualization method proposed in this study, namely weighted average visualization (WAV), is tailored to meet specific characteristics of the aforesaid dataset and is capable of discovering patterns that are not visible through current approaches.

Abstract: The increase in the demand for sand and gravel for construction and other purposes such as flood control has placed immense pressure on the environment where sand and gravel resources occur. This study was carried out to determine the environmental effects of sand and gravel mining in Luku, North central Nigeria, using field observations and laboratory analysis of soil samples. Field work was carried out in the area to determine the physical environmental effects of mining while soil samples were analysed at the National Geo-science Research Laboratory (NGRL) of Nigerian Geological Survey Agency (NGSA), Kaduna for trace elements using X-Ray Fluorescence (XRF) method. Result of the field observations shows that destruction of landscape, reduction of farm and grazing land, collapsing river banks, deforestation and water pollution are the environmental effects that result due to sand and gravel mining in the area. Result of the chemical analysis shows that average concentrations of Pb, As, Cu, Ni, Cd, Hg, Ag and Zr are 47.8, 4.17, 50.9, 32.7, 2.48, 0.1, 0.8 and 496.1ppm respectively. These concentrations are higher than the average standard concentrations of these elements found in the upper continental crust. These higher concentrations may have very negative effects on plants and animals in the area and cause diseases such as brain and kidney damage, lung irritation, cardiac abnormality and event death to plants and animals.

Abstract: Geological and geotechnical investigation along River Bosso, Minna to determine the soil characteristics contributing to gully erosion in the area was done. Field mapping showed that granite, granite-gneiss and schist of Basement complex suite underlie the area and granite is more prominent than granite-gneiss and schist. The index test results for the natural moisture content ranges from 11.19 – 24.08%; the plasticity index ranges from 0 – 5.21%; the sieve analysis result shows that coefficient of uniformity, C_u ranges from 3.37 and 29.00 while coefficient of curvature, C_c ranges from 0.17 – 0.89; the undisturbed bulk density is between 0.87 – 1.11kg/m³ and the compacted bulk density is between 1.25 – 1.49kg/m³; the specific gravity ranges from 2.16 - 2.67. For the performance test; the compaction result shows that the optimum moisture content (OMC) ranges from 8.90 – 14.85% while the maximum dry density (MDD) ranges from 1.880 - 2.09mg/m³; the triaxial shear test result shows that the angle of internal friction is between 6⁰ - 9⁰ and the cohesion ranges from 28 – 42kg/m²; the permeability is between 1.42 × 10^-3 and 1.93 × 10^-3 cm/sec. The relatively high sand content and low plasticity of the soil is susceptible to erosion which is attributed to the dominant granitic rock of the study area with high affinity for gully erosion. The anthropogenic factors found to have contributed to gully growth are farm practice, mining activities and residential buildings on the flood plain.

Abstract: The famous iron formation of north Odisha belongs to the Archaean schist belt comprising of the litho assemblages including the Banded Iron Formation (BIF), Iron Ore and associated rocks. Major iron formations are confined to three different provinces located in the peripheral region encircling the granite complex, which is designated as the North Odisha Iron Ore Craton (NOIOC). These three iron ore belts are intra-cratonic basins that act as depository sites for the BIF, iron ore and associated rocks. The tectonic setting is correlated with the iron ore orogeny and suffered post tectonic deformations. The rocks of all the three belts have undergone multiple phases of deformation including folds and faults. The fold structures in successive phases are superimposed to produce numerous interference patterns.