Waterflood Management of a Super Giant Carbonate Mauddud Reservoir, Raudhatain Field, North Kuwait

Abstract

Raudhatain Mauddud is an oil bearing carbonate reservoir in North Kuwait. Mauddud consists of 10 layers with different fluid properties (API from 30 to 14 Deg). Oil production started in year 1957 till year 2000 when started full filed waterflood project. There was quick and clear positive response to water injection in both reservoir pressure and oil production. However there was early water breakthrough in some wells. Many factors have increased challenges in managing Mauddud waterflood project. These challenges were mainly due to reservoir heterogeneity in all layers, structure, injection of low saline water, difficulty to evaluate remaining potential in flooded wells or to identify thief zone before start the injection. Consequently, the water management strategy has been adapted by implementing methods and tools to tackle these challenges. Interwell tracers have been implemented to study and monitor water movement from the injectors to the producers and evaluate the sealing nature of the faults. Pattern x-section including Tracer, PLT and production data has been used under one page to assist in evaluating and studying water movement within the reservoir. Automated Workflow has been established to calculate VRR for each pattern. Surveillance plan has been implemented including inference tests and PBU/PFO. The injection to production connections and profiles has been modified by isolating top intervals in the injectors and drill horizontal injectors in the bottom of the reservoir. The new horizontal producer has been drilled in the top of the reservoir with advanced completion technology of ICD. Managing Mauddud Waterflood project in that way has resulted in increase of total Mauddud daily oil rate by 20% with drop in water cut from 40 to 33%. This paper is summarizing the methods that have been used to manage Raudhatain Mauddud waterflood project as best practices.