Grane PRM Project - Following the Footsteps of a Successful 4D Story

The Grane oil field is located in the Norwegian North Sea, about 200 km NW of Stavanger, Norway and contains heavy (19°API), high viscosity, biodegraded and under saturated oil with no initial gas cap. The expected oil in place volumes amounts to about 221 Mill.Sm³ and the expected ultimate recovery are 142 Mill.Sm³. The field has been successfully produced since the start-up in September 2003, and the present production is approximately 75,000 barrels of oil per day. 4D Monitoring program was initiated in 2005 to map reservoir dynamics. Accordingly, the field has been under monitoring till date with acquisition of conventional streamer seismic data every second year. Based on the need for more frequent monitoring, a permanent reservoir monitoring (PRM) system has been installed in Grane in 2014 with 300m cable separation and 50m between receivers. Initial plan exists to monitor the reservoir every 6 months.