In a small area in the western part of the Alta-Kvænangen window it has been possible to reveal the presence of a minimum of six basaltic lava layers separated by tuff/tuffite beds. The lavas have well-preserved primary structures including pillow lava, columnar jointing, pillow breccia, and pipe vesicles, while massive lava lacking specific structures is common. The tuff/tuffite beds exhibit sedimentary bedding, graded bedding, and cross-bedding. Available evidence indicates a subaquatic 'mise en place' for all the rocks of Middavarre.
Precambrian primary volcanic structures in the Alta-Kvænangen tectonic window, northern Norway