Geology of Norway

The geology of Norway encompasses the history of earth that can be interpreted by rock types found in Norway, and the associated sedimentological history of soils and rock types.

The Norwegian mountains were formed around 400 million years ago (Ma) during the Caledonian orogeny.

Rocks of Archean age in Norway are confined to a few 10 km-scale areas within younger metamorphic belts exposed on islands off the west coast of northern Norway and as smaller fragments locally in the Western Gneiss Region in south-central Norway.

Despite intense reworking during the Caledonian orogeny in some areas, three major belts can be recognised in the Proterozoic rocks of Norway, the Neoproterozoic and Mesoproterozoic Gothian and Sveconorwegian, the Palaeoproterozoic Svecokarelian and the intervening Transscandinavian Igneous Belt of late Palaeoproterozoic age. About 1400 million years ago in the Mesoproterozoic tectonic extension and continental magmatism led to the formation of Kattsund-Koster dyke swarm in southeastern Norway.

The later part of the Neoproterozoic records the break-up of the Rodinia supercontinent and the formation of the Iapetus Ocean. Passive margin sequences are preserved within the lowermost allochthon and parautochthon of the Caledonian thrust sheets. In southern Norway the sequence is known as Sparagmite. The depositional environment changes from fluvial in the parautochthon to deepwater marine in the lowermost allochthon consistent with a paleogeography of an originally westward deepening basin.

...
Wikipedia