Water Injection Optimization in mature fields using low-cost techniques: North Sea field Case

Gorm is a complex water-flooded chalk reservoir located in the Danish sector of the North Sea. The field has undergone a series of depletion, gas injection and then followed by water injection. Water injection has been on the decline in the recent years due to depleting well stock and integrity issues. Hence it was imperative to optimize water injection using the existing well stock. Thus, SRT’s (Step Rate Tests) were conducted in all Gorm active water injection wells in 2018 and early 2019.

Performing SRT’s on all the Gorm injection wells allowed us to assess the current fracture pressure, safely enabling an update of the water injection targets resulting in better voidage by optimum pressure support.

Based on this campaign of SRTs on Gorm the WI potential with the current well stock has been increased by 11% thereby providing better pressure support to the reservoir without damaging the formation. Following the SRT campaign, the water injection in the Gorm field has plateaued with a small decrease in 2020 due to further depletion of injection well stock. Hopefully the success of the last campaign should trigger a new SRT campaign in Gorm in 2022.