The Heidrun Field: monitoring fluid flow in the complex Åre Formation

The Heidrun Field, offshore mid-Norway is compartmentalized by a large number of faults and stratigraphic barriers, making prediction of flow and contact movements difficult, especially in the complex Åre Formation. In 2006, a time-lapse seismic survey was conducted over the north flank of the field giving, for the first time, the opportunity to monitor fluid movements in the Åre Formation. Using these time-lapse data, evidence of communication across faults and across the stratigraphy has been obtained and we discuss two examples for the Åre Formation. The observations in the Åre Formation have increased the understanding of flow movements and given valuable input for identifying new drainage points. In addition, the results have led to a revision of the field’s injection strategy. Integrated work by a team of geophysicists, reservoir engineers, and geologists has resulted in a total of 22 flooding maps, including 13 new maps for the Lower Tilje Formation and the Åre Formation.