Historical seismicity of the Faroe Islands

Abstract

A study is presented of the historical seismicity of the Faroe Islands, an area of low seismicity where no previous search for historical earthquakes was ever made. This presents a novel problem, since most studies of historical seismicity usually have previous catalogues to use as starting points. In this case the only information available at the start of the study related to a short sequence of small events in 1967 and two newspaper reports from the 1920s-1930s of strange phenomena which could be discounted from being earthquake related. The methodology of researching historical seismicity from scratch is described in detail. The results of the study were that no genuine historical earthquakes were found. However, in the first case, the fact that no events were found indicates that the lack of historical events in the Faroes is real and not just a function of no-one ever having looked for them before. In the second case, a positive statement (from 1906, in connection with a spurious earthquake report) was found that no earthquakes were known ever to have occurred in the Faroes. This means that two types of argument can be adduced: that there is no evidence that there were earthquakes (argument from the negative), and that there is evidence that there weren’t earthquakes (argument from the positive). Taking into consideration the historical and cultural factors, some limits are drawn up for the probable extent to which one can rule out the occurrence of earthquakes of different intensities for different time periods.