The melting of the most recent ice sheet caused massive faulting and earthquakes (M7 or more on the Richter scale) in northern Sweden and neighbouring areas of Finland and Norway. These earthquakes triggered hundreds of landslides in moraine, and also created extensive deformation structures in the loose soil deposits.

No conclusive proof has been found of similar periods of faulting in conjunction with earlier glacial periods in northern Sweden, where the limited glacial erosion of the land ought to have allowed any fault scarps to be preserved. This suggests that the history of seismic activity in the Earth's crust during the most recent glaciation differs from that during previous glacial periods.

Deformations that may have been caused by earthquakes have also been found in sandy and silty sediments in southern and central Sweden, although they are not particularly common there. South of the northern Swedish province of Västerbotten there are no unequivocal signs of major faulting from the end of the most recent glaciation. This does not mean that no faulting is present, but it does suggest that any faulting will be less extensive than in northern Sweden.

Knowledge of these faulting processes is needed to assess the safety of planned deep bedrock nuclear waste repositories, among other things.

The report can be ordered from SGU (see ordering and contact details below). The whole publication can also be downloaded in PDF format via the link further down the page.