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The aim of this research is to establish the significant effect of environmental factors on malaria prevalence rate within the Local Government Areas of Lagos State. The methodology used was to carry out a statistical analysis of these various environmental factors with the malaria prevalence cases that was recorded in Lagos State using a 5 years data from 2009-2013 of malaria prevalence cases recorded with environmental data for the same time frame, and to further use GIS to show the various Local Government Areas with high severe malaria cases as well as low malaria cases. The result obtained from this analysis shows a significant relationship between the malaria prevalence cases and environmental factors of rainfall, temperature and relative humidity, this helped in developing a predictive model. The outcome from this research work can help the government, Lagos State Ministry of Health and donor agencies both local and international see the Local Government Areas within the state that are most vulnerable to malaria epidemic, and further aid them in policy formation, planning and strategy implementation.

Productivity through groundwater is quite high as compared to surface water, but groundwater resources have not yet been properly exploited. The present study is used to delineate various groundwater potential zones for the assessment of groundwater availability in Lagos metropolis using remote sensing and GIS and hydrogeophysics techniques. Landsat 8, SRTM, geological, soil, and rainfall data were used in the study to prepare various thematic maps, viz., geomorphological, slope, soil, lineament density, rainfall and land use maps. On the basis of relative contribution of each of these maps towards groundwater potential, the weight of each thematic map have been selected and assigned to each map. Hydrogeophysics investigation using Vertical Electric Sounding (VES) was applied to validate the remote sensing and GIS results. All the thematic maps have been registered with one another through ground control points and integrated using the weighted overlay method in GIS for computing groundwater potential index. Based on the methological approach, the ground water potential zones were delineated. The results showed that there are five categories of groundwater potential zones within the study area in which percentage values were contained in each of the categories thereby making major portion of the study area “high” and “moderate” prospect while a few scattered areas have “low” prospect. The very high potential areas are mainly concentrated along the River Alluvium while the “very low” prospect are majorly where there is sand and clay. The best groundwater potential zone is in the southern part due to the presence of fractures, swamp soils which have high infiltration ability and the presence of waterbody which is chiefly accountable for the groundwater recharge in any area. The VES data showed the depth of the aquifer for good water and the polluted aquifer within the study area.

The isostatic residual gravity anomaly data of Gongola basin was computed by removing from the Bouguer gravity anomaly field, a regional gravity field calculated for compensation of masses of surface topography. The regional gravity field was computed using the Airy-Heiskanen isostacy model with compensation at the crust-mantle discontinuity. The free air, residual isostatic anomaly, density distribution maps and 2.5D gravity models were utilized in the definition of the basin's crust-mantle structures. Results showed that: (1) the free air anomaly depicted the edge effect anomaly which correlates with the slope and rise at the NE zone. (2) The isostatic residual anomaly showed three zones: the overcompensated (NE-SE), undercompensated (NW-SW) while the hydrostatic equilibrium zone was found to be the transition between the undercompensated and the overcompensated zones. The distribution of rock densities within the exposed crust is not unimodal. The main component is the granodioritic ones 3 2.65 2.72 / g cm consisting of plutonic rocks. The granitic component 3 2.60 2.64 / g cm is common within the subsurface. The high velocities (6.2 /) km s and the modeled high densities from 3 2.78 2.83 / g cm suggest that the materials comprises high-grade metamorphic mafic intrusive and volcanic rocks. (3) The change in the crustal thickness along the profiles due to intra sediment and basement intrusive provide a measure of the amount of heating that occurred during rifting. Thus, the gravity across the rift system is found to be due to upwelling of low density hot materials which has also affected the hydrocarbon in place. (4) The crustal thickness together with the depositional architecture (e.g. porosity and permeability) should be used to determine the subsurface fluid circulation in terms of hydrocarbon exploration within the rifted basin. The intrusives are potential targets for solid minerals.

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