Paleoseismic characteristics: the Swedish case
by
Nils-Axel Mörner
Paleogeophysics & Geodynamics

Only by considering paleoseismic data do we obtain a long-term record of the seismic activity allowing meaningful seismic hazard predictions for time periods longer than one to a few centuries. In the Swedish case, the analysis reveals a drastic change in dominant seismic mode; viz. from a high to super-high deglacial mode to a low to moderately low mode today and in Late Holocene time. Paleoseismic criteria and characteristics include numerous different sources of information; viz. primary faults, bedrock deformation, sedimentary deformation, rock and sediment slides, liquefaction, sorting by shaking, tsunami waves, a number of different geomorphic expressions, paleomagnetic disordering as well as ordering. By applying multiple criteria, it was possible to identify and separate 42 paleoseismic events into a paleoseismic catalogue at present including 21 events of M6-7, 12 events of M7-8 and 6 events of M>8. Varve-dating often allows a precision as to a single year, in one case even to the season of a year. The key-tool is the application of multiple criteria.

Date received: February 28, 2002

Copyright © 2002 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caiq-29.