الفهرس 
Chapter One - IntroductionOnly 14 pages are availabe for public view
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Abstract
Different hydraulic fracturing applications can be applied in the same field, furthermore, same well. Comparing these applications practical implementation and post-fracturing results are the indications towards application optimization. Different applications of hydraulic fracturing stimulation were performed on the fields under study with props and cons for each application. Hydraulic fracturing without proppant flow-back controller was the primitive fracturing application. Although the post-hydraulic fracturing production rates were very encouraging, the production was not sustained as proppant started to flow back in some of these wells and several workover operations were required to clean-out wellbores. Also, many of the down hole pumps failed due to proppant flow-back. In addition, the proppant pack stability was affected by low formation closure stress, drag forces resulting from higher drawdown applied by down-hole pumps and the viscous oil properties of the low gravity oil being produced. Fiber addition to the proppant tailing stages was then considered to control flow-back of proppant following the fracturing treatments. The first fibrous immobilized proppant flow-back control material was used in two wells. These two wells came back strong with the expected fluid production rates and proppant flow-back was controlled to a certain extent. However, the main drawback in using fibrous flow-back control materials was the occurrence of several coiled tubing BHA plugging incidents that resulted in extended clean-out operations and additional workover costs as well as problems associated with mixing and pumping fibers with conventional proppant in surface pumping equipment. Rod shaped proppant tailing was then applied to improve the hydraulic fracture packing stability and enhance the fracture conductivity. Rod shaped proppant provided superior proppant flow-back control in many wells due to its shape which improved the fracture packing stability and post-fracturing coiled tubing clean-out operations. The optimum amount of this proppant to be pumped was then studied and determined. The up-to-date pumping technology of intermittent pumping pulses between proppant-added and free from proppant pumping sessions was then applied in order to improve the fracture proppant packing distribution and accordingly the fracture conductivity. Through the aforementioned applications, the first multistage hydraulic fracturing stimulation in horizontal well in Egypt was executed and results were evaluated. As a step towards hydraulic fracturing optimization and better understanding of hydraulic fracture propagation through the fields under study, modeled fracture height validation was done by open hole versus cased hole advanced sonic logging and comparing the shear waves anisotropy naturally occurring in the formation pre-fracturing job with the post-fracturing job anisotropy. Fracture confinement within the zone of interest as the upper and lower formations acted as stress barriers for fracture propagation was then confirmed. New mechanical earth model was interpreted to the lithological column of one well which was then taken as being the typical one for the whole field where stress deviations were then modified. Better pre-fracturing job modeling was then done which helped significantly in the post-fracturing geometry simulation. This study helped in enhancing the overall hydraulic fracturing stimulations and the optimum design for each well can be easily determined with less well interventions and accordingly the costs associated with these workovers. The performance of the fracture itself is improved in terms of formation fluids production sustainability and fracture packing reliability.