The Fangst Group - Not Formation
The Not Formation (Aalenian to Bajocian) is developed as a mudstone dominated sequence coarsening upwards into bioturbated fine-grained sandstones deposited in lagoons or sheltered bays. The Not Fm is recognised over the entire Haltenbanken area, except on the eroded highs. The thickest development (<50m) of the Not Fm is on the southwestern part of the Halten Terrace, and the unit thins towards the east. On the Trøndelag Platform it has a consistent thickness of approximately 40m. The mudstones of the Not Fm could act as a seal.
In the type well (6507/1-3) the thickness is 14.5m and 37m in the reference well (6407/1-3).