Norwegian offshore formations reclassified to support CO2 storage

The Norwegian Offshore Directorate (NOD) has reviewed about 800 wells in the Utsira Group and the Skade Formation in the North Sea to support planning of CO₂ storage.

In the younger part of the stratigraphic sequence, there are large volumes of sand in the area between the Sleipner field in the south and the Møre Basin at 62° north, much of it deposited during the Miocene era.

Until now, the industry has shown little interest in the sands due to the small volumes of gas proven by some wells, but that is changing due to the emergence of the carbon capture and storage industry.

In 2022, the NOD published a revised classification and naming protocol for these sands. However, the formation tops listed in the FactPages of its website were not consistent with the revisions, making them hard to use for mapping of storage potential.

That has changed following the review of the wells. In areas where the sands are strongly re-mobilized and form injectites, “No formal name” applies, so the formation names only occur once in each well.

The NOD has also added tops for the Pleistocene sands in the Snotra Formation and Tampen Spur member, neither of which were previously published.