Published: 05.08.2015 | Author: Haakon Fossen
This little mountain in the picture sticks up because the layers are tilted on their sides. The new road cuts right through the folds in a longitudinal direction. Dark amphibolite- and biotite layers together with lighter layers of gneiss make the layers easily visible. (Svein Nord)
FOLDS: NATURE'S ART
Fantastic folding structures in banded gneiss have come to light in road cuts along the new road from Toftøyna, just north of the intersection to Vik. Such structures give a dramatic picture of the strong forces that once were at work deep down under the earth's crust. Similar folding is seen several places in the gneisses west and northwest of Bergen, in the area where the gneiss layers now stand on edge. The folds are a result of movements in the bedrock at the end of the Caledonian Mountain Building event. Then, these layers lay at great depth, where they got turned on their sides and squeezed together into fine folds. Most often, the layers are quite flat-lying in Øygarden, with a gentle slope toward the east.
- Johns, C. J. 1981. The geology of northern Sotra; Precambrian gneisses west of the Bergen Arcs, Norway. Ph.D.avhandl., Bedford College, Univ. of London.