Grunnfjellsvinduer i Dividalen, Troms.
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- Artikler 
Two small windows of Precambrian granites were investigated during a few days the summer 1962. Above the granites there follow autochtonous rocks of the Hyolithes Zone, of Lower Cambrian age. On the autochtonous rocks rests a metamorphic nappe of quartz schist, mica schist and meta-limestones. The lower parts of the quartz schist, just above the autochtonous rocks, are mylonitized and folded. Tectonization phenomena are also to be seen many places in the Hyolithes rocks. There are two types of Precambrian granites in the windows: an older one with grey to white colour, and a younger red granite which sends veins into the former. The mineral composition is about the same in both, the colour difference of the rocks is due to differences in colour of the feldspars. The older granite is weathered along the contact to the overlying Cambrian rocks. There are some signs of tectonization in the granites. The Hyolithes Zone rocks consist of: an arkosic sandstone (at the bottom), shales (mostly red, green or grey in colour) and a thick sequence of sandstones (about 50 m). The whole sequence is about 77 m thick and can be correlated with the lower and middle parts of Hyolihes Zobne sequences in other parts of the Troms and Finnmark counties. The higher part of the zone is lacking in Dividalen.