Wintershall has shut-in the Maria field since February, approximately a year after first production, following poor production performance. It is understood that reserves have been downgraded from 207mmbbl to c.60 mmbbl.
The field is now undergoing testing and monitoring to see how best to produce the remaining reserves the recover the lost reserves whilst managing the reservoir. It is understood that the NPD has to review plans and sign off on the field's restart for fear unintended reservoir damage. There is currently uncertainty on whether the field will start up again.
The cause is believed to be poor connectivity between zones. Water injection is provided to the zone below for pressure support. However analysis is now showing low connectivity between the geological layers in the reservoir, and thus the water injection is not working effectively.
Wintershall started production from the Maria oil field on Haltenbanken in the Norwegian Sea in December 2017, one year ahead of schedule and with 20% reduction in costs. Maria was Wintershall’s first own-operated field in Norway.
Wintershall chose an innovative subsea concept to develop the field. Two subsea templates were installed on the seabed above the Maria reservoir and connected via a pipeline network to the existing Kristin, Heidrun, and Åsgard B platforms.
