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Abstract
This paper gives a survey of the Proterozoic rocks in central Värmland and neighbouring areas to the north. Special attention is given to the Östmark formation of volcanics and sedimentary rocks including the Hålsjöberg quartzite. The predominant rocks of the region are three generations of tectonized Svecokarelian granitoids called gneiss-granites. These seem to be younger than the sedimentary rocks of the Östmark formation. Still younger rocks in the region are a group of post-Svecokarelian Värmland granitoids, a black diabase known as hyperite, and the Gräsmark Formation of volcanics. All rocks mentioned have been tectonized twice during the final Precambrian orogenesis, viz. the Dalslandian (Sveconorwegian). Moreover, the older gneiss-granites have been tectonized during the Svecokarelian.