Karna Lidmar-Bergström

I have worked with the relationships between the forms of the Precambrian bedrock and cover rocks of different age directly on basement. This is unique in the world.

There are two types of denudation surfaces, the re-exposed and the epigene. The re-exposed surfaces in Sweden are the sub-Cambrian flat peneplain and the sub-Jurassic/Cretaceous hilly etchsurfaces. The epigene surfaces are plains with residual hills in stepped sequences. The two re-exposed surfaces are divided into blocks and inclined in different directions. The epigene surfaces are horizontal.

The subject originates in Sweden from the old field geologists, but early it was taken over by the geographers. The geographers both made maps of the relief differentiation of the major bedrock forms and interpretation maps of the forms in their relation to cover rocks. The major figures were Sten De Geer and Sten Rudberg in Gothenburg but also Åke Mattsson in Lund, my teacher, was a prominent figure. The first two wrote for the Geological Survey and constructed maps and text for university geography text books. The results from all of them were also incorporated in a book summarizing Swedish geology. However, it is not in the new textbook on Swedish geology, as no geologist was able to write it. Bedrock geomorphology does not exist anymore neither in Sweden or in an international context, since about the year 2000.

I have used a method, where I combined closely space digital profiles (N-S and E-W, for every 5th km in south Sweden and every 10th kilometer in north Sweden) and related them to cover rocks of different ages, both aerially and, where possible, in the third dimension. My interpretation gave partly a new picture and also covered all of Sweden. The results were mainly used for tectonic conclusions.

The denudation surfaces are landscapes, whose forms are dependent of their closeness to former covers, but the denudation surfaces are never identical with their related unconformity. They have undergone certain changes, but their inclination and relief amplitude are still recognizable in the profiles. Thus glacial erosion must therefore have been limited.

I have also used the knowledge I have obtained for conclusions on uplift and invented a method, Stratigraphical Landscape Analyses, based on my knowledge from particularly southern Sweden.

Important references for Swedish geomorphology with particular reference to the formation  primary peneplain (the sub-Cambrian) and the  importance of deep weathering for later landform development:

Elvhage, C., & Lidmar-Bergström, K., 1987: Some working hypotheses on the geomorphology of Sweden in the light of a new relief map. Geografiska Annaler 69(A):343-358.

Lidmar-Bergström, K., 1988: Denudation surfaces of a shield area in south Sweden. Geografiska Annaler 70A(4):337-350.

Lidmar-Bergström, K., 1989: Exhumed Cretaceous landforms in south Sweden. Zeitschrift für Geomorphologie, N.F. Suppl. bd 72:21-40.

Lidmar-Bergström, K. 1991: Phanerozoic tectonics in southern Sweden. Zeitschrift für Geomorphologie, N.F. Suppl. bd 82:1-16.

Lidmar-Bergström, K., 1993: Denudation surfaces and tectonics in the southernmost part of the Baltic Shield. Precambrian Research 64:337-345.

Lidmar-Bergström, K., 1994: Berggrundens ytformer (Morphology of the bedrock surface). In Sveriges Nationalatlas (National Atlas of Sweden), Berg och jord (Geology). Temared. Curt Fredén. P. 44-54.

Lidmar-Bergström, K., 1995: Relief and saprolites through time on the Baltic Shield. Geomorphology 12 (1): 45-61. In Special issue on Pre-Glacial landforms. Ed. K. Lidmar-Bergström.

Lidmar-Bergström, K., 1996: Long term morphotectonic evolution in Sweden. Geomorphology 16: 33-59.

Lidmar-Bergström, K., Olsson, S. & Olvmo, M., 1997: Palaeosurfaces and associated saprolites in southern Sweden. In Widdowson, M. (ed.): Palaeosurfaces: recognition, reconstruction and environmental interpretation. Geological Society London. Special publication. 120: 95-124.

Lidmar-Bergström, K., 1997: A long term perspective on glacial erosion. Earth surface processes and landforms. 22: 297-306.

Johansson, M., Olvmo, M. and Lidmar-Bergström, K., 2001. Inherited landforms and glacial impact of different palaeosurfaces in southwest Sweden. Geografiska Annaler 83A: 67-89.

Migon, P., & Lidmar-Bergström, K., 2001: Weathering mantles and their significance for geomorphological evolution of central and northern Europe since the Mesozoic. Earth Science Reviews. vol. 56, pp. 285-324.

Lidmar-Bergstöm, K. & Näslund, J., 2005: Fennoscandia – Major landforms and bedrock. In: Seppälä, M. (ed.): The Physical Geography of Fennoscandia. The Oxford Regional Environments Series, Oxford University Press. Pp 3-18.

Olvmo, M., Lidmar-Bergström, K., Ericson, K. & Bonow, J., 2005. Saprolite remnants as indicators of pre-glacial landform genesis in southeast Sweden. Geografiska Annaler 87A, 447 – 460.

Lidmar-Bergström, K. and Olvmo, M., 2015. Plains, steps, hilly relief and valleys in northern Sweden – review, interpretations and implications for conclusions on Phanerozoic tectonics. Sveriges Geologiska Undersökning Research Paper C 838, 42 pp.

Lidmar-Bergström, K., Olvmo, M. & Bonow, J.M., 2017. The South Swedish Dome: a key structure for identification of peneplains and conclusions on Phanerozoic tectonics of an ancient shield. GFF 139, 249-259.

Important references for uplift studies

Lidmar-Bergström, K., Bonow, J.M., Japsen, P., 2013. Stratigraphic Landscape Analysis and geomorphological paradigms: Scandinavia as an example of Phanerozoic uplift and subsidence. Global and Planetary Change 100, 153-171.

Green, P.F., Lidmar-Bergström, K., Japsen, P., Bonow, J.M., Chalmers, J.A., 2013. Stratigraphic landscape analysis, thermochronology and the episodic development of elevated, passive continental margins. Geological Survey of Denmark and Greenland Bulletin 2013/30, 150 pp.