Abstract: Introduction:Building a large number of static models to analyze reservoir performance is vital in reservoir development planning. For the purpose of maximizing oil recovery, reservoir behavior must be modelled properly to predict its performance. This requires the study of the variation of the reservoir petrophysical properties as a function of spatial location.Methods:In recent times, the method used to analyze reservoir behavior is the use of reservoir simulation. Hence, this study seeks to analyze the spatial distribution pattern of reservoir petrophysical properties such as porosity, permeability, thickness, saturation and ascertain its effect on cumulative oil production. Geostatistical techniques were used to distribute the petrophysical properties in building a 2D static model of the reservoir and construction of dynamic model to analyze reservoir performance. Vertical to horizontal permeability anisotropy ratio affects horizontal wells drilled in the 2D static reservoir. The performance of the horizontal wells appeared to be increasing steadily as kv/kh increases. At kv/kh value of 0.55, a higher cumulative oil production was observed compared to a kv/kh ratio of 0.4, 0.2, and 0.1. In addition, horizontal well length significantly affects cumulative oil production of the petroleum reservoir studied.Results:At kv/kh of 0.55, the results of the analysis showed a rapid decrement in cumulative oil production as the horizontal well length decreases. Considering horizontal well length of 3000 ft, 2000 ft, and 1500 ft, a minimum cumulative oil production was obtained from a horizontal well length of 1500 ft.Conclusion:The geostatistical and reservoir simulation methods employed in this study will serve as an insight in analyzing horizontal well performance.
Abstract: Introduction:A good hole cleaning operation is an important factor for every successful drilling program. Drilling mud should be formulated to suspend and transport cuttings effectively to minimize the number of drill cuttings in the hole. It is therefore, essential to determine the best weighing material that would be incorporated into the drilling mud for efficient hole cleaning given the well’s condition and formation type.Methods:This work is aimed to provide a detailed comparative analysis on the effect of drilling mud weight, using different concentrations of barite and calcium carbonate as weighing materials to determine optimum materials for hole cleaning.Results and Discussion:The results show that barite gave a lower annular pressure drop and therefore, a better Equivalent Circulating Density (ECD) compared to calcium carbonate, though, calcium carbonate gave better results in terms of transport efficiency and cutting concentration compared to barite.Conclusion:Barite is highly applicable in high-pressure reservoirs and calcium carbonate is applicable in depleted reservoirs. It can also serve as a bridging agent and can be used in reservoirs where it is necessary to minimize formation damage.