Abstract

In this study we present the results of an updated and checked seismic catalog of the northern Fennoscandian region, specifically the area which contains the Postglacial faults (PGFs) from the Merasjärvi Fault System in the southwest to the Iešjávri Fault System in the northeast. This work has been done through an exhaustive revision of continuous waveforms, which were obtained from open-data sources between the period 2006 to 2015, and processed with the algorithm Regressive ESTimator (REST). The motivation of this study is to better delineate the seismicity path along the mentioned PGFs, recognizing their seismic potential. As a result, we observed different waveforms produced by mainly two sources: the greatest seismic activity in the area comes from events of mining origin, which represent nearly 80% of the events recorded by the seismological stations. On the other hand, nearly 13% of earthquakes come from areas where the PGFs have been mapped. The increase considering already reported catalogs was around 20% of seismic events in PGFs areas, and 55% of seismic events with mining origin. These results show that the use of REST autopicking program not only allows to recover tectonic seismicity but also helps to identify seismic events associated with induced activity. The Merasjärvi, Lanio-Suijavaara, Palojärvi, Maze and Iešjávri fault systems appear from the new earthquake catalog to be located within a c. 300 km long and continuous deformation complex that we suggest being termed at the Merasjärvi-Stuoragurra Fault Complex.