South Swedish highlands
The South Swedish highlands or South Swedish Uplands (Swedish: Sydsvenska höglandet) is a hilly area covering large parts of Götaland in the southern parts of Sweden. Except for a lack of deep valleys the landscape is similar to the Norrland terrain found further north in Sweden.
Much of the highlands lies above 200 m.a.s.l. and there are large areas around the highlands that exceed 100 m.a.s.l. The highlands are centered on Småland but cover also large swathes of Scania, Halland, Västergötland, Östergötland and Blekinge. The highest point lies 377 m a.s.l.
Within a geological context the highlands are the expression of the South Swedish Dome. The South Swedish Dome has been subsided and been uplifted multiple times by epeirogenic movements during the Phanerozoic. The dome has had periods of subsidence and burial in sediments have alternated with periods of exhumation and the formation of peneplains and hilly relief. The Sub-Cambrian peneplain of Late Neoproterozoic age is the oldest of the surfaces. It covers the eastern and northern flanks of the dome and its crest region where it is up-broken. The mesozoic-aged Sub-Mesozoic hilly relief covers the southern and western fringes of the dome, corresponding roughly with the counties of Halland, Blekinge and northeastern Scania. The youngest well-defined surface is the South Småland peneplain that formed in the Neogene. In detail the South Swedish Dome has the form of a piedmonttreppen or staircase of erosion surfaces. From top to bottom the levels are:
- the crestal and upbroken portions of the Sub-Cambrian peneplain
- the 300 m a.s.l. peneplain[A]
- the 200 m a.s.l. peneplain, containing various inselbergs.[B]
- the South Småland peneplain (175–125 m a.s.l.)[C]
- the 100 m a.s.l. surface which is part of the South Småland peneplain
The Late Cenozoic uplift of the dome is tentatively related to far-field compressional stresses that has uplifted the region as a giant anticline-like lithosphere fold. As such it is similar to uplifted passive margins like the Scandinavian Mountains or the mountains of Western and Eastern Greenland.
During the last deglaciation of the Weichselian Ice Sheet the South Swedish highlands were a place of ice flow divergence. Deglaciation of southern Sweden was relatively slow with ice margin retreat rates of less than 150 m/yr. The retreat was interrupted multiple times by small glacier advances. These advances led to the formation of a series of end moraine systems. During deglaciation in southern Sweden glacier ice was mostly warm-based with some lesser parts being cold-based.
- This level was considered as part of a post-Silurian peneplain by Sten Rudberg as it could be matched to hills in Västergötland (Kinnekulle, Halleberg, Hunneberg and Billingen). Karna Lidmar-Bergström consider this correlation plausible but the evidence tenuous.
- The existence of this surface was first noted by S. Nordlindh in 1924 in a monograph about hydropower and topography.
- The South Småland peneplain was first noted by Sten De Geer in 1913.
- Lidmar-Bergström, Karna; Olvmo, Mats; Bonow, Johan M. (2017). "The South Swedish Dome: a key structure for identification of peneplains and conclusions on Phanerozoic tectonics of an ancient shield". GFF.
- Lundqvist, Jan (1969). "Landskapet". In Lundqvist, Magnus. Det Moderna Sverige (in Swedish). Bonniers. pp. 64–67.
- Åkerhielm, Erik (1912). "Sydsvenska höglandet". Geografien i skildingar och bilder (in Swedish). Lund. pp. 49–90. Retrieved June 7, 2015.
- Lidmar-Bergström, Karna; Bonow, Johan M.; Japsen, Peter (2013). "Stratigraphic Landscape Analysis and geomorphological paradigms: Scandinavia as an example of Phanerozoic uplift and subsidence". Global and Planetary Change. 100: 153–171.
- Japsen, Peter; Green, Paul F.; Bonow, Johan M.; Erlström, Mikael (2016). "Episodic burial and exhumation of the southern Baltic Shield: Epeirogenic uplifts during and after break-up of Pangaea". Gondwana Research. 35: 357–377.
- Lidmar-Bergström, Karna. "Sydsvenska höglandet". Nationalencyklopedin (in Swedish). Cydonia Development. Retrieved November 30, 2017.
- Lidmar-Bergström (1988). "Denudation surfaces of a shield area in southern Sweden". Geografiska Annaler. 70 A (4): 337–350.
- Japsen, Peter; Chalmers, James A.; Green, Paul F.; Bonow, Johan M. (2012). "Elevated, passive continental margins: Not rift shoulders, but expressions of episodic, post-rift burial and exhumation". Global and Planetary Change. 90–91: 73–86.
- Lundqvist, Jan; Lundqvist, Thomas; Lindström, Maurits; Calner, Mikael; Sivhed, Ulf (2011). "Svekokarelska Provinsen". Sveriges Geologi: Från urtid till nutid (in Swedish) (3rd ed.). Spain: Studentlitteratur. p. 515. ISBN 978-91-44-05847-4.
- Stroeven, Arjen P.; Hättestrand, Clas; Kleman, Johan; Heyman, Jakob; Fabel, Derek; Fredin, Ola; Goodfellow, Bradley W.; Harbor, Jonathan M.; Jansen, John D.; Olsen, Lars; Caffee, Marc W.; Fink, David; Lundqvist, Jan; Rosqvist, Gunhild C.; Strömberg, Bo; Jansson, Krister N. (2016). "Deglaciation of Fennoscandia". Quaternary Science Reviews. 147: 91–121.