|Location:||22km north of Mo i Rana.|
|Open:||15-JUN to 20-AUG daily 10-19. Tour every hour on the hour.|
|Fee:||Adults NOK 60, Children NOK 30. Groups: Adults NOK 50.|
|Classification:||horizontal cave in marble.|
|Guided tours:||D=30min, L=400m, V=8,000/a.|
Stein-Erik Lauritzen, Hilde Hestangen, Sara M. Skutlaberg, Rannveig Øvrevik (2005):
The Grønli-Seter cave research project, Rana, North Norway,
14th International Congress of Speleology. Athen-Kalamos 21-28 aug. 2005 paper P-22.
|Address:||Grønli, 8615 Skonseng, Tel: +47-75-162305.|
|As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.
|1914||first survey by the norwagian geologist Oxaal.|
|1988||investigation of cave sediments by StPierre and Løvlie.|
The limestone of this area was folded and transformed into marble during the caledonian orogenesis. Today it builds a thin band of marble enbedded into layers of schist. The layer falls with about 20°, the cave follows this layer.
In many parts of the cave, the ceiling is formed by the overlying schist. This ist very easy to see: as the schist is not soluble by the water, the ceiling is actually the extremely flat layer boundary.
The cave was first formed as a subaquatic cave below the water table, but soon the water table lowered and a river widened the cave. The walls show typical forms of erosion.
In a room called Chapel a huge block of granite is found. As the next granite is several kilometers away, the block somehow must have been transported into the cave. The theory says, that 10.000 years ago, at the end of the ice age, the melting water of an enormous glacier, transported the granite into Grønligrotta.