Seismic Structure of Earth’s Crust in Finland

  • Pekka HeikkinenEmail author
Part of the Lecture Notes in Earth Sciences book series (LNESS, volume 137)


During the last three decades, the Earth’ crust in Finland has been extensively studied using seismic refraction/wide angle surveys, near vertical reflection profiling and tomographic measurements, with profiles and networks covering most of the territory of Finland. A major change in the seismic structure of the crust occurs along the Lake Ladoga – Bothnian Bay zone. In the velocity models NE of the zone the crustal thickness varies from 40 to 48 km, whereas in SW underneath the Svecofennian orogen, the thickness can reach values over 60 km. In general, all the crust is reflective, but there is a clear change across the zone. In SW lower crustal reflectivity is diffuse whereas in the north it is strong, with a clear base of reflectivity at the MOHO. Based on reflectivity, the crust is composed of blocks with sizes varying from tens of kilometers to a couple of hundred kilometers. This block structure is also visible in the tomographic 3D velocity models.

The seismic studies have significantly improved understanding of the crustal structure and evolution of the Fennoscandian Shield, showing that the same plate tectonic processes which are active today in the Earth formed the Fennoscandian shield 2 billion years ago.


Continental Crust Oceanic Crust Lower Crust East African Rift Polar Profile 
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  1. BABEL Working Group (1990) Evidence for early proterozoic plate tectonics from seismic reflection profiles in the Baltic Shield. Nature 348:34–38CrossRefGoogle Scholar
  2. Bock G, SVEKALAPKO Seismic Tomography Working Group (2001) Seismic probing of archaean and proterozoic lithosphere in Fennoscandia. EOS T Am Geophys Un 82:628–629Google Scholar
  3. Christensen NI, Mooney WD (1995) Seismic velocity structure and composition of the continental crust: a global view. J Geophys Res 100:B9761–B9766CrossRefGoogle Scholar
  4. Daly JS, Balagansky VV, Timmerman MJ, Whitehouse MJ (2006) The Lapland-Kola orogen: Palaeoproterozoic collision and accretion of the northern Fennoscandian lithosphere. In: Gee DG, Stephenson RA (eds) European lithosphere dynamics. Geological Society London Memoirs 32:561–578Google Scholar
  5. Grad M, Tiira T, ESC Working Group (2009) The Moho depth map of the European plate. Geophys J Int 176:279–292. doi: 10.1111/j.1365-246X.2008.03919.x CrossRefGoogle Scholar
  6. Hyvönen T, Tiira T, Korja A, Heikkinen P, Rautioaho E, the SVEKALAPKO Seismic Tomography Working Group (2007) A tomographic crustal velocity model of the central Fennoscandian Shield. Geophys J Int 168:1210–1226CrossRefGoogle Scholar
  7. Korja A, Heikkinen P (2005) The Accretionary Svecofennian Orogen – insight from the BABEL profiles. Precambrian Res 136:241–268CrossRefGoogle Scholar
  8. Korja A, Heikkinen P (2008) Seismic images of Paleoproterozoic microplate boundaries in the Fennoscandian Shield. In: Condie KC, Pease V (eds) When did plate tectonics begin on planet Earth? Geological Society of America, Special paper 440: 229–248Google Scholar
  9. Kukkonen IT, Heikkinen P, Ekdahl E, Hjelt S-E, Yliniemi J, Jalkanen E, FIRE Working Group (2006) Acquisition and geophysical characteristics of reflection seismic data on FIRE transects, Fennoscandian Shield. In: Kukkonen IT, Lahtinen R (eds) Finnish reflection experiment FIRE 2001–2005 Geological Survey of Finland, Special paper 43:13–43Google Scholar
  10. Kuusisto M, Kukkonen IT, Heikkinen P, Pesonen LJ (2006) Lithological interpretation of crustal composition in the Fennoscandian Shield with seismic velocity data. Tectonophysics 420:283–299CrossRefGoogle Scholar
  11. Lahtinen R, Korja A, Nironen M (2005) Palaeoproterozoic tectonic evolution. In: Lehtinen M, Nurmi P, Rämö T (eds) The Precambrian Geology of Finland – key to the evolution of the Fennoscandian Shield. Elsevier, Amsterdam, pp 418–453Google Scholar
  12. Luosto U (1997) Structure of the Earth's crust in Fennoscandia as revealed from refraction and wide-angle reflection studies. Geophysica 33(1):3–16Google Scholar
  13. Patison NL, Korja A, Lahtinen R, Ojala J, the FIRE Working Group (2006) FIRE seismic reflection profiles 4, 4A and 4B: Insights into the crustal structure of Northern Finland from Ranua to Näätämö. In: Kukkonen IT, Lahtinen R (eds) Finnish reflection experiment FIRE 2001–2005 Geological Survey of Finland, Special paper 43:161–222Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  1. 1.Institute of SeismologyUniversity of HelsinkiHelsinkiFinland

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