Tehostekuvassa fysiikan laitosta etuoven suunnalta

2. Meteorite impact research


The maps represents the location of the eleven impact structures in Finland (left) and 31 in Fennoscandia (right)



Impact map of Fennoscandia Learn more about them:
1. Lappajärvi
2. Sääksjärvi
3. Söderfjärden
4. Iso-Naakkima
5. Lumparn
6. Suvasvesi N
7. Karikkoselkä
8. Saarijärvi
9. Paasselkä
10. Suvasvesi S
11. Keurusselka
Impact map of Fennoscandia

Participating scientists

  • L.J. Pesonen, project leader
  • J. Salminen
  • T. Öhman (U of Oulu)
  • S. Raiskila, PhD student
  • W.U. Reimold (Humboldt University, Berlin, Germany)
  • R.L. Gibson (University of Witwaterstrand, South Africa)
  • P. Rochette (University of Aix-Marseille III, France)
  • S. Mertanen (Geological Survey of Finland)

Project goals

To search and study meteorite impact structures around the world. As a result of the "focused" impact search strategy, where geophysics played a major role, we have found seven new impact structures in Finland during the last 15 years.

Highlights

In Finland eleven meteorite impact structures are proven, i.e., these sites reveal petrological, geophysical geochemical and morphological features, which are characteristic of places struck by an extraterrestrial projectile. The bulk diameter of the structures varies between about 1.3 and 23 km, and their age from Mesoproterozoic (~1140 Ma) to Late Cretaceous (~73 Ma). Seven of them have been discovered or confirmed since 1989 during the "great impact search project".

Recent publications

  • Pesonen L.J., 2010. Meteorite impact cratering - its geological and geophysical significance, with a focus on Fennoscandia. In: Laakso, K., Kultti, S., and Salonen, V-P. National Geological Colloquium 2010 Abstracts. Department of Geosciences and Geography, University of Helsinki, Helsinki University Print, Helsinki, p. 38.
  • Krøgli, S.O., Dypvik, N., Chicarro, A., Rossi, A.P., Pesonen, L.J. and Etzelműller, B., 2008. Application of crater discovery tool on terrestrial data, Finnmark, Norway. In: Abstracts of the 33rd International Geological Congress, Oslo. Abstract No. GTR01603L.
  • Dypvik, H., Plado, J., Heinberg, C., Håkansson, E., Pesonen, L.J., Schmitz, B. and Raiskila, S., 2008. Impact a structures and events - a Nordic perspective. Earth System Science: Foundation for Sustainable Development. Special Issue for the 33rd International Geological Congress, Oslo, Norway, 6-14 August, 2008. Episodes, Vol.31, (No.1), 107-114.
  • Pilkington, M. Pesonen, L.J., Grieve, R.A.F. and Masaitis, V., 2002. Geophysics, petrophysics and paleomagnetism of the Popigai impact structure, Siberia. In: Plado, J. and Pesonen, L.J. (eds.), Impacts in Precambrian Shields, Springer Verlag, 87-108.
  • Abels, A., Plado J., Pesonen, L.J., Lehtinen, M., 2002. The Impact Cratering Record of Fennoscandia. In: Plado, J. and Pesonen, L.J. (eds.), Impacts in Precambrian Shields, Springer Verlag, 1-58, Vol.31, (No.1), 107-114.