الفهرس 
Chapter One IntroductionOnly 14 pages are availabe for public view
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Abstract
Well productivity decline have been widely observed for gas wells producing the reservoir fines. The phenomenon has been explained by the theory of drawdown, migration and subsequent plugging of the pores by the fine particles, finally resulting in permeability decrease. It has been observed in numerous core flood tests and field cases. The studied field is a gas field in the North-western margin of the Nile Delta. It is a gas field with current production capability of 0.8 Bscf/d. It has the potential to produce above this level with the current stock of wells but have only been limited to this through-put due to considerable losses in well productivity that the wells have experienced in recent years. This research project is three fold: first, studying reservoir studies and production analysis to understand the reasons for the considerable losses in productivity of the wells. Second, evaluating core flood test analysis to define the size, shape and composition of the mobile fines. Third, evaluating matrix acidizing to override the productivity losses due to fines migration. Reservoir studies indicated that the productivity losses in the studied field wells are consequences of skin build-up overtime in most of the wells while in other wells, the losses are combined effects of skin build-up and effective KH reductions due to the mobile fines that affect the total productivity of the wells. Core flood tests showed that fines migration is likely to occur in the studied field, if the operational sequence evaluated in this study is deployed in the wells and the formation fines can mobilize in the formation and concentrate in the near wellbore area, resulting in pore throats becoming occluded and thus leading to a reduction in permeability and production decline. The evaluation of the case study of acid matrix stimulation showed that the improvement is limited to few inches in the formation beyond the wellbore region and this may allow future fines re-invasion into the near wellbore. So the recommended treatment for fines is a combination of acidizing to dissolve fines, enlarge pore-throat size to diminish near wellbore particle bridging and consolidation of the formation to lock in place those fines that are not removed by the treatment and prevent future fines re-invasion.