This study focuses on the application of 3D static model using 3-D seismic and well log data for proper optimization and development of hydrocarbon potential in KN field of Niger Delta Province. 3D Seismic data were used to generate the input interpreted horizon grids and fault polygons. The horizon which cut across the six wells was used for the analysis and detailed petrophysical analysis was carried out. Structural and property modeling (net to gross, porosity, permeability, water saturation and facies) were distributed stochastically within the constructed 3D grid using Sequential Gaussian Simulation and Sequential Indicator Simulation algorithms. The reservoir structural model show system of different oriented growth faults F1 to F6. Faults 1 and Fault 4 are the major growth faults, dipping towards southwest and are quite extensive. A rollover anticline formed as a result of deformation of the sediments deposited on the downthrown block of fault F1. The other faults (2, 3, 5 and 6) are minor fault (synthetic and antithetic). The trapping mechanism is a fault assisted anticlinal closure. Results from well log analysis and petrophysical models classified sand 9 reservoir as a moderate to good reservoir in terms of facies, with good porosity, permeability, moderate net to gross and low water saturation. The volumetric calculation of modeled sand 9 horizon reveals that the (STOIIP) value at the Downthrown and Ramp segment are 15.7 MMbbl and 3.8 MMbbl respectively. This implies that the mapped horizon indicates hydrocarbon accumulation in economic quantity. This study has also demonstrated the effectiveness of 3-D static modeling technique as a tool for better understanding of spatial distribution of discrete and continuous reservoir properties, hence, has provided a framework for future prediction of reservoir performance and production behavior of sand 9 reservoir. However, more horizontal wells should be drilled to enhance optimization of the reservoir.

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ABSTRACT:The study was carried out to investigate the dissimilar seismic amplitude responses observed in sandstone reservoirs with the same fluid saturation. This challenge now informed the analysis of different amplitude responses from the 'Jay' Field in order to verify the reservoirs fluids around and away from well location based on the integration of Amplitude Variation with Angle (AVA) and seismic inversions. The well log data provided were used to identify hydrocarbon bearing zones and Poisson Ratio analysis. Anomalies from the AVA analysis were investigated using the elastic impedance inversion of the near and far volumes. Crossplots of Lambda-Mu-Rho inversion were produced to relate reservoir incompressibility and rigidity modulus for lithology and fluid determination. Sand E exhibited amplitude increase with angles at well point and also away from well location (red triangle). The approximate elastic impedances of the inverted seismics are almost similar to the log estimates, an indication of good correlation. Integration of incompressibility (Lambda-Rho) and rigidity (Mu-Rho) modulus analyses reveals the presence of gas saturation in reservoir Sand G because low Lambda-Rho coincides with high Mu-Rho from both log estimates and inverted seismics. In the case of Sand D, high Lambda-Rho coincides with high Mu-Rho because it is oil saturated. This study has helped to differentiate the fluids in Sands D and G despite having similar AVA responses. The methods adopted in this work can be useful in hydrocarbon detection from seismic data in fields with similar geological setting. Seismic inversion technique helps in the determination of reservoir properties away from well location (Simm, 2005). For instance, inverted seismic data enhances the identification of subtle properties in conventional seismics (Contreras et al., 2006). Reservoir properties between wells can be determined from inverted seismic results. This was demonstrated by Adekanle and Enikanselu, (2013) where the vertical and lateral extent of rock properties such are porosity, lithology and density were determined. However, seismic data have limited frequency content such that thin layers may not be resolved (Simm and Bacon, 2014).The integration of high frequency log information with seismic data in model based inversion was adopted to mitigate this effect. Moreover, model based inversion technique of iterative forward modeling and comparison procedure does not suffer from defective wavelet and over simplification of the subsurface associated with recursive and sparse spike inversions methods respectively (Cooke and Schneider, 1983;Veeken and Da Silva, 2004;Simm and Bacon. 2014).The integrated approach of Lambda-Mu-Rho inversion and Rock Physics modeling by Ekwe et al., (2012) was used to delineate hydrocarbon charged reservoirs in a Niger Delta field. In gas hydrates region where well information is most often sparse, Amplitude Variation with Angle (AVA) was the method used for free hydrate gas assessment as discussed by Javaherian et al., (201...

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ABSTRACT:In the past few decades, disposal sites have been filled with household refuse and different kinds of potentially dangerous industrial waste in an uncontrolled manner which poses an enormous risk for the environment, and are the main sources for groundwater contamination. With the aim of assessing impact of leachate on the underlying aquifers by determining and delineating possible leachate infiltration into the aquifer matrix ,Constant Spacing Traversing (CST) was carried out using Wenner array and spacing between 10-60 m along four 160 m -180 m profiles. The results revealed the aquifer is characterized by low resistivity response generally below 4.5 ohm-m depicting possible contamination of the underlying aquifer from Oke-Odo landfill. The surface of the waste landfill is characterized by differential decomposition of waste as zones of advanced decomposition and fresh waste are reflected as low and high resistivity respectively. The absence of leachate in the aquifer 100 m from the studied area suggests that the leachate has not spread to this area, therefore, safe for groundwater exploitation. This study demonstrated the expeditiousness and effectiveness of the resistivity technique as a tool for geo-environmental mapping of leachate. @JASEM