The Alta-Kvaenangen window consists of a precambrian basement (Raipas Group), with a eo-cambrian autochthonous cover (Bossekop and Borras Group) consisting of sandstones, schists and tillite. These autochthonous units are overthrusted by the caledonian nappes. This was established at the beginning of the century.
This work emphasizes the precambrian group of Raipas (divided into two sub-groups). Its total thickness is 2-2, 5 km.
The lower sub-group (Lower Raipas) consists of intrusive and submarine volcanic rocks, of basaltic composition, sometimes with a tendency to spilites. These rocks are interbedded with volcano-sedimentary rocks (tuffs s .1. ) and argillites and dolomites. The metamorphic grade belongs to the "greenschist facies group". The K/Ar age on diabases and lavas is approx. 1, 4·109 years.
The upper sub-group (Upper Raipas) consists of a formation of sandstones and a formation of alternating dolomite and sandstone at the top. We suggest the names of "Skoadduvarri formation" for the sandstones formation and "Luovusvarri formation" for the alternating dolomite and sandstone formation.
The tectonic style of the Raipas group has been established mainly from the way-up criterions of the pillow-lavas, - in the absence of fossils - and also from sedimentation figures such as ripple-marks, graded beddings, cross bedding.
The part of the Alta-Kvaenangen window studied here is divided into 3 different tectonic areas:
1- the NW area, with its isoclinal folding;
2- the middle area, characterised by WNW-ESE faults with medium dips SSW or NNE, and limited by 2 SSW-NNE faults;
3- the NE area with big open folds.
Sorne aspects of the Quaternary geology are also mentioned: the surrection of Scandinavia can be noticed from ancient shore lines and marine terraces. Visible glacial and periglacial phenomenons are moraines, boulder fields and different kinds of polygonal patterns, these latters being observed only in high and remote areas.
