Fractured injection is not new to the oil and gas industry, and occurs unintentionally in most water injection schemes. However, deliberate fractured water injection is usually not evaluated upfront in order to derive optimal cost and recovery, and open-up opportunities for further optimization. The initial design for water flooding in Barton was based on a full-blown conventional water treatment plant on a new platform for seawater injection under matrix conditions.
Fracture simulation work revealed that in the case of Barton, by relaxing water quality induced fractures are not expected to be excessively large and cause any concerns on integrity of the reservoir and nearby wells. Owing to a lower required injection tubing head pressure than previously believed to achieve fractured injection only relatively low pressure and cheap injection pumps are required. Additionally, fractured water injection has allowed for the introduction of raw-seawater injection, whereby the significantly smaller water treatment facility than previously required for matrix injection is placed on a deck extension from an existing platform.