Advertisement

Rock-Avalanche Activity in W and S Norway Peaks After the Retreat of the Scandinavian Ice Sheet Open image in new window

  • Reginald L. HermannsEmail author
  • Markus Schleier
  • Martina Böhme
  • Lars Harald Blikra
  • John Gosse
  • Susan Ivy-Ochs
  • Paula Hilger
Conference paper

Abstract

We have compiled recently published and unpublished cosmogenic 10Be exposure ages of rock-avalanche deposits and break away scars in western and southern Norway in order to compare those to the retreat of the Scandinavian ice sheet. In total 22 rock-avalanche events were dated by their deposits (19) or break away scars (3). Sampling of rock-avalanche deposits and failure surfaces was not systematic over the region but with few exceptions we sampled all deposits within the same valley. All ages were recently calculated using the CRONUS online calculator and the geochronology ensemble reveal five late Pleistocene events, eight Preboreal events, and nine younger events. The decay of the Scandinavian ice sheet was not spatially synchronous but differed regionally and lasted over several thousand years in places, hence the requirement for widespread dating targets. One rock avalanche (at Innerdalen at 14.1 ka) occurred when ice existed in the valley, which is in agreement with the latest deglacial models. Depositional characteristics of ten (44%) of the rock avalanches suggest ice free conditions although they occurred within the first millennia following local deglaciation. Five events (22%) occurred between 9 and 7.5 ka at a time when climate was warmer and moister than today. Finally seven events (30%) appear to be relatively evenly distributed throughout the rest of the Holocene. Although limited in number we interpret that the dated events are representative of the temporal distribution of post-ice sheet rock avalanches in western Norway. However, the number of rock avalanches occurring onto the decaying ice sheet is likely underrepresented as those deposits are reworked and can be difficult to distinguish from moraine deposits. Our widespread data reveal a rapid rock slope instability response to the initial local decay of the Scandinavian ice sheet followed by a lower and constant frequency following the climate optimum (ca. 8.5 ka) in the Holocene.

Keywords

Decay of the scandinavian ice sheet Cosmogenic nuclide Surface exposure dating Rock-avalanche deposit Late pleistocene Holocene Preboreal Fast response 

Notes

Acknowledgements

Field work and age determination of samples taken in 2003 were financed through the Excellence Centre “International Centre for Geohazards” financed by the Norwegian Research Council. Later samples were taken partly financed through the Norwegian Water Resources and Energy Directorate (NVE) and partly through a Ph.D. thesis by M. Schleier. R.L. Hermanns got funding to write this publication through the NFR-funded CryoWALL project (243784/CLE).

References

  1. Aa AR, Sjåstad J, Sønstegaard E, Blikra LH (2007) Chronology of Holocene rock-avalanche deposits based on Schmidt-hammer relative dating and dust stratigraphy in nearby bog deposits, Vora, inner Nordfjord, Norway. The Holocene 17:955–964CrossRefGoogle Scholar
  2. Antinao JL, Gosse J (2009) Large rockslides in the Southern Central Andes of Chile (32–34.5 S): tectonic control and significance for quaternary landscape evolution. Geomorphology 104:117–133CrossRefGoogle Scholar
  3. Ballantyne CK, Sandeman GF, Stone JO, Wilson P (2014) Rock-slope failure following Late Pleistocene deglaciation on tectonically stable mountainous terrain. Quatern Sci Rev 86:144–157CrossRefGoogle Scholar
  4. Blikra LH, Longva O, Braathen A, Anda E, Dehls JF, Stalsberg K (2006) Rock slope failures in Norwegian fjord areas: examples, spatial distribution and temporal pattern. In: Evans SG, Scarascia Mugnozza G, Strom A, Hermanns RL (eds) Landslides from massive rock slope failure. NATO science series IV: earth and environmental sciences 49. Springer, Dordrecht. pp 475–496Google Scholar
  5. Böhme M, Oppikofer T, Longva O, Jaboyedoff M, Hermanns RL, Derron MH (2015) Analyses of past and present rock slope instabilities in a fjord valley: implications for hazard estimations. Geomorphology 248:464–474CrossRefGoogle Scholar
  6. Böhme M, Hermanns RL, Oppikofer T, Fischer L, Bunkholt HSS, Eiken T, Pedrazzini A, Derron M-H, Jaboyedoff M, Blikra LH, Nilsen B (2013) Analyzing complex rock slope deformation at Stampa, western Norway, by integrating geomorphology, kinematics and numerical modelling. Eng Geol 154:116–130CrossRefGoogle Scholar
  7. Braathen A, Blikra LH, Berg SS, Karlsen F (2004) Rock-slope failures of Norway, type, geometry deformation mechanisms and stability. Nor Geol Tidsskr 84:67–88Google Scholar
  8. Cruden DM, Hu XQ (1993) Exhaustion and steady state models for predicting landslide hazards in the Canadian rocky mountain. Geomorphology 8:279–285CrossRefGoogle Scholar
  9. Gosse JC, Phillips FM (2001) Terrestrial in situ cosmogenic nuclides: theory and application. Quatern Sci Rev 20:1475–1560CrossRefGoogle Scholar
  10. Hermanns RL, Oppikofer T, Anda E, Blikra LH, Böhme M, Bunkholt H, Crosta GB, Dahle H, Devoli G, Fischer L, Jaboyedoff M, Loew S, Sætre S, Yugsi Molina F (2013) Hazard and risk classification system for large unstable rock slopes in Norway. In: Genevois R, Prestininzi A (eds) International conference on Vajont—1963–2013. Ital J Eng Geol Environ, Book series 6:245–254Google Scholar
  11. Hermanns RL, Longva O (2012) Rapid rock-slope failures. In: Clague JJ, Stead D (eds) Landslides: types, mechanisms and modeling. Cambridge University Press, Cambridge, UK, pp 59–70CrossRefGoogle Scholar
  12. Hermanns RL, Fischer L, Oppikofer T, Böhme M, Dehls JF, Henriksen H, Longva O, and Eiken T (2011) Mapping of unstable and potentially unstable rock slopes in Sogn og Fjordane, NGU rapport 2011.055, 195 pGoogle Scholar
  13. Hermanns, RL, Blikra LH, Longva O (2009) Relation between rockslide dam and valley morphology and its impact on rockslide dam longevity and control on potential breach development based on examples from Norway and the Andes, Long term behavior of dams.In: Proceedings of the 2nd international conference, Graz, Austria. pp 789–794Google Scholar
  14. Hewitt K, Gosse J, Clague JJ (2011) Rock avalanches and the pace of late quaternary development of river valleys in the Karakoram Himalaya. Geol Soc Am Bull 123:1836–1850CrossRefGoogle Scholar
  15. Hughes ALC, Gyllencreutz R, Lohne ØS, Mangerud J, Svendsen JI (2016) The last Eurasian ice sheets—a chronological database and time-slice reconstruction, DATED-1. Boreas 45:1–45CrossRefGoogle Scholar
  16. Korup O, Clague JJ, Hermanns RL, Hewitt K, Strom AL, Weidinger JT (2007) Giant landslides, topography, and erosion. Earth Planet Sci Lett 261:578–589CrossRefGoogle Scholar
  17. Saintot A, Oppikofer T, Derron M-H (2012) Large gravitational rock slope deformation in Romsdalen valley (Western Norway). Revista de la Asociación Geológica Argentina 69:354–371Google Scholar
  18. Schleier M, Hermanns RL, Rohn J, Gosse J (2015) Diagnostic characteristics and paleodynamics of supraglacial rock avalanches, Innerdalen, Western Norway. Geomorphology 245:23–39CrossRefGoogle Scholar
  19. Schleier M, Hermanns RL, Gosse JC, Oppikofer T, Rohn J, Tønnesen JF (2016) Subaqueous rock-avalanche deposits exposed by post-glacial isostatic rebound, Innfjorddalen, Western Norway. Geomorphology. (in press)Google Scholar

Copyright information

© Springer International Publishing AG 2017

Authors and Affiliations

  • Reginald L. Hermanns
    • 1
    • 2
    Email author
  • Markus Schleier
    • 3
  • Martina Böhme
    • 1
  • Lars Harald Blikra
    • 4
  • John Gosse
    • 5
  • Susan Ivy-Ochs
    • 6
  • Paula Hilger
    • 1
  1. 1.Geological Survey of NorwayTrondheimNorway
  2. 2.Department of Geoscience and PetroleumNorwegian University of Science and TechnologyTrondheimNorway
  3. 3.GeoZentrum NordbayernUniversity of Erlangen-Nuremberg ErlangenErlangenGermany
  4. 4.Norwegian Water and Energy DirectorateTrondheimNorway
  5. 5.Department of Earth SciencesDalhousie UniversityHalifaxCanada
  6. 6.ETH ZurichInstitute for Particle PhysicsZurichSwitzerland

Personalised recommendations