1. Formerly Equinor ASA, Wessels veg 41, 7502 Stjørdal, Norway; presently Aker BP ASA, Munkegata 26, 7011 Trondheim, Norway.(corresponding author).
2. Formerly Equinor ASA, Martin Linges vei 33, 1364 Fornebu, Norway; presently TGS-NOPEC Geophysical Company, Askekroken 11, 0277 Oslo, Norway..
3. Equinor ASA, Forusbeen 50, Stavanger 4035, Norway..