Note on the basement-cover relationship of the Visingsö group in the northern part of the Lake Vättern basin, south Sweden

Abstract

Abstract Thin layers of yellow sandstone and some sandstone dikes have been found on a gently dipping, unweathered surface of granite on the northeastern shore of the island Stora Roknen in the northem part of Lake Vattern. The granite is penetrated by local shear zones with a ‘western-side-up’ sense of shear, typical for the Protogine zone in the region. The sandstone dikes fill fractures oriented along the shear zones and the layers of fine-grained sandstone rest discordantly on the sheared granite, which demonstrates a considerable hiatus between the shear zone development and the dcposition of the sandstone.