Earthquakes in Switzerland and surrounding regions during 2017 and 2018

Abstract This report summarizes the seismicity in Switzerland and surrounding regions years 2017 2018. In 2018, Swiss Seismological Service detected located 1227 955 earthquakes region under consideration, respectively. The strongest event analysed period was M L 4.6 Urnerboden earthquake, which occurred border of cantons Uri, Glarus Schwyz on March 6, 2017. earthquake within since 5.0 Vaz 1991. Associated ground motions indicating intensity IV were reported a radius up to about 50 km locally approached VI close epicentre. Derived focal mechanisms relative hypocentre relocations immediate aftershocks image NNW–SSE striking sinistral strike-slip fault. Together with other past events this region, suggests existence system sub-parallel faults, likely uppermost crystalline basement eastern Aar Massif. A vigorous sequence Château-d'Oex Préalpes-Romandes western Switzerland. With magnitude 4.3, July 1, Focal mechanism fore- NNE dipping normal fault 4 depth. Two similarly oriented shallow normal-fault between subalpine Molasse Préalpes units Châtel-St-Denis St. Silvester 2017/18. Together, these indicate domain NE–SW extensional transtensional deformation along Alpine Front Lake Geneva west Fribourg Fault east. structural complexity is revealed by an 2.9 near Tafers images NW–SE segment basement, might be related Zone. Finally, 2.8 Grenchen provides rare example thrust faulting Jura fold-and-thrust belt, contraction northwestern foreland