LIQUEFACTION AND VARVE DEFORMATION AS EVIDENCE OF PALEOSEISMIC EVENTSAND TSUNAMIS - THE AUTUMN 10,430 BP CASE IN SWEDEN

Coastal seismic events generate instantaneous changes in relative sea level (i.e. land level vs sea level). Tsunamis may cause disastrous da mage to coasts and coastal habitation. Liquefaction and deformations o f annually varved sediments provide information on paleoseismic events . The evidence for a major earthquake and associated tsunami waves in Sweden are explored. Thanks to the varve chronology, liquefaction stru ctures and varve deformations caused by this event can be dated at the autumn 10,430 varve years BP. The magnitude is estimated at 8 (or mor e) on the Richter scale. The tsunami washed the previously blocked out let of the Baltic free of icebergs and pack-ice so that marine water c ould suddenly invade the entire Baltic, forming the Yoldia Sea. Copyri ght (C) 1996 Elsevier Science Ltd