Halleberg
Coordinates: 58°23′N 12°27′E / 58.383°N 12.450°E
Halleberg is a table mountain by lake Vänern in Vänersborg Municipality, Västergötland, Sweden.
Halleberg, part of which protrudes into Lake Vänern is separated in the south by about 500 m (1,600 ft) wide valley from the adjacent Hunneberg (although this is a table mountain). The northern part of Halleberg called Hallesnipen.
Hallberg has an average height of about 90 m (300 ft) above lake Vänern, or 134 ft (41 m) above sea level; the highest point is 155 m (509 ft) above sea level.
Halleberg consists of Cambrian, Ordovician and Permian rocks. The Palaeozoic rocks are deposited directly on the crystalline peneplain bedrock, which in this range consists of göta granite. The Cambrian sedimentary rocks are sandstone and alum shale. The sandstone layer is on average 24 m (79 ft) thick. Above this there is then a 0.3 m (0.98 ft) thick slate which in turn covered by about 24 m (79 ft) of alum shale. The Ordovician is represented by a calcareous slate. During the Permian it was pushed into diabase which lays as a protective cover and thus protect the mountain from erosion. The diabase on Västgötabergen known locally for staircases.
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