Our research in Svalbard began in 1975 as a cooperative project with the Polish Academy of Sciences, and the University of Bergen. The project was funded by the Office of Polar Programs of the National Science Foundation. The Norwegian Polar Institute, the University of Hamburg, and NORSAR later joined the cooperative effort. In the first year of the project, Seweryn Duda, Stanislaw Vincenz and I were the co-investigators from SLU. Seweryn moved to the University of Hamburg after one year and I became the scientific leader. Stanislaw conducted research on paleomagnetism and my main contribution was mapping of the seismicity in Svalbard. The Norwegian Polar Institute and NORSAR joined our effort to map Svalbard seismicity in 1979. SLU students and I also participated in data collection for two crustal scale seismic refraction studies in Svalbard for which the main contributors were the Polish Academy of Sciences, the University of Bergen, and the University of Hamburg. Contributors to the project included four faculty and staff members and fourteen students from SLU, as well as numerous personnel from four Norwegian and German institutions.

Svalbard is an archipelago on the northwestern corner of the Barents Shelf. It lies less than 150 km from portions of the Atlantic Ridge system to the west and less than 500 km from the Nansen (or Gakkel) Ridge to the north. Its crustal thickness and seismic velocities are typical of continental regions (Chan and Mitchell, 1982). It therefore provided us the opportunity to study earthquake activity and present-day tectonics in a relatively stable continental platform which lies in close proximity to spreading plate boundaries.

Spitsbergen is the largest island of the archipelago with Nordaustlandet, Barentsoya, and Edgeoya being other relatively large islands lying to the east. Spitsbergen is traversed by several major north-south trending fault zones. The most important of these is the Billifjorden fault zone which is mapped over about 2/3 the length of the island. The main zones of seismic activity do not lie on the trends of any of the mapped faults on the island of Spitsbergen, but do lie on mapped faults on the island of Nordaustlandet. Station locations changed from year to year over the several years of recording.

A summary map of seismicity between 1977 and 1986 shows the three major concentrations of earthquake activity that we found in Svalbard. One of these is the Heer Land seismic zone on the eastern coast of Spitsbergen, and the other two lie in northwestern Nordaustlandet. Low levels of seismic activity occur throughout much of the rest of the archipelago.

Assorted Photos - Click on miniature for an enlarged version and description.

1976 - 1978
Temporary earthquake recording and collecting seismic refraction data

1979 - 1981
Continuously operating telemetered stations for earthquake recording

1982 - 1986
Temporary earthquake recording on Nordaustlandet and northern Spitsbergen

Selected Publications

Bungum, H., B.J. Mitchell, and Y. Kristoffersen, Concentrated earthquake zones in Svalbard, Tectonophysics, 82, 175-188, 1982.

Chan, W.W., Structure and tectonics of the Barents Shelf, Ph.D. diss., Saint Louis University, 234 pp., 1983.

Chan, W.W., and B.J. Mitchell, Synthetic seismogram and surface wave constraints on crustal models of Spitsbergen, Tectonphysics, 89, 51-76, 1982.

Chan, W.W., and B.J. Mitchell, Surface wave dispersion, crustal structure, and sediment thickness variations across the Barents shelf, Geophys. J. R. Astr. Soc., 80, 329-344, 1985.

Chan, W.W., and B.J. Mitchell, Intraplate earthquakes in northern Svalbard, Tectonophysics, 114, 181-191, 1985.

Mitchell, B.J., S.A. Vincenz, R. Teisseyre, A. Guterch, S. Duda, and M. Sellevoll, Geophysical research on Spitsbergen, Arctic Bull. (published by the National Science Foundation), 2, 314-319, 1978.

Mitchell, B.J., and W.W. Chan, Characteristics of earthquakes in the Heer Land zone of eastern Spitsbergen, Polarforschung, 48, 31-40, 1987.

Mitchell, B.J., J.E. Zollweg, J.J. Kohsmann, J.J. Cheng, and E.J. Haug, Intraplate earthquakes in the Svalbard Archipelago, J. Geophys. Res., 84, 5620-5626, 1979.

Mitchell, B.J., H. Bungum, W.W. Chan, and P.B. Mitchell, Seismicity and present-day tectonics of the Svalbard region, Geophys. J. Int., 102, 139-149, 1990.

 

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