The evolution of western Scandinavian topography: A review of Neogene uplift versus the (isostasy-climate-erosion) hypothesis

Autor: Erik Thomsen, Callum Leighton, Michael A. Summerfield, Kerry Gallagher, Ole R. Clausen, Holger Lykke-Andersen, Niels Abrahamsen, Bo Holm Jacobsen, Niels Balling, Nielsen Ole, Søren Bom Nielsen, Mads Huuse, David L. Egholm, Marianne R. Thorsen, Chris King, Claus Heilmann-Clausen, Lasse Svenningsen, Jan A. Piotrowski
Přispěvatelé: Géosciences Rennes (GR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Rennes (OSUR), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)
Jazyk: angličtina
Rok vydání: 2009
Předmět:
Zdroj: Journal of Geodynamics
Journal of Geodynamics, 2009, 47 (2-3), pp.72-85. ⟨10.1016/j.jog.2008.09.001⟩
Nielsen, S B, Gallagher, K, Leighton, C, Balling, N, Svenningsen, L, Jacobsen, B H, Thomsen, E, Nielsen, O B, Heilmann-Clausen, C, Egholm, D L, Summerfield, M, Clausen, O R, Piotrowski, J A, Thorsen, M R, Huuse, M, Abrahamsen, N, King, C & Lykke-Andersen, H 2009, ' The evolution of western Scandinavian topography: A review of Neogene uplift versus the ICE (isostasy–climate–erosion) hypothesis ', Journal of Geodynamics, vol. 47, pp. 72-95 .
Journal of Geodynamics, Elsevier, 2009, 47 (2-3), pp.72-85. ⟨10.1016/j.jog.2008.09.001⟩
Aarhus University
ISSN: 0264-3707
DOI: 10.1016/j.jog.2008.09.001⟩
Popis: International audience; Tectonics and erosion are the driving forces in the evolution of mountain belts, but the identification of their relative contributions remains a fundamental scientific problem in relation to the understanding of both geodynamic processes and surface processes. The issue is further complicated through the roles of climate and climatic change. For more than a century it has been thought that the present high topography of western Scandinavia was created by some form of active tectonic uplift during the Cenozoic. This has been based mainly on the occurrence of surface remnants and accordant summits at high elevation believed to have been graded to sea level, the inference of increasing erosion rates toward the present-day based on the age of offshore erosion products and the erosion histories inferred from apatite fission track data, and on over-burial and seaward tilting of coast-proximal sediments. In contrast to this received wisdom, we demonstrate here that the evidence can be substantially explained by a model of protracted exhumation of topography since the Caledonide Orogeny. Exhumation occurred by gravitational collapse, continental rifting and erosion. Initially, tectonic exhumation dominated, although erosion rates were high. The subsequent demise of onshore tectonic activity allowed slow erosion to become the dominating exhumation agent. The elevation limiting and landscape shaping activities of wet-based alpine glaciers, cirques and periglacial processes gained importance with the greenhouse­icehouse climatic deterioration at the Eocene­Oligocene boundary and erosion rates increased. The flattish surfaces that these processes can produce suggest an alternative to the traditional tectonic interpretation of these landscape elements in western Scandinavia. The longevity of western Scandinavian topography is due to the failure of rifting processes in destroying the topography entirely, and to the buoyant upward feeding of replacement crustal material commensurate with exhumation unloading. We emphasize the importance of differentiating the morphological, sedimentological and structural signatures of recent active tectonics from the effects of long-term exhumation and isostatic rebound in understanding the evolution of similar elevated regions.
Databáze: OpenAIRE
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