A Two-Station Seismic Method to Localize Glacier Calving

Abstract

A method of determining glacier calving location using seismic wave arrival times from paired local seismic stations is presented. The difference in surface wave arrival times for each pair is used to define a locus (hyperbola) of possible origin. With multiple pairs, this can be used to triangulate for the origin of the seismic wave, which is interpreted as the calving location. This method is motivated by difficulties with traditional seismic location methods that fail due to the emergent nature of calving, which obscures the P and S- wave onsets, and the proximity of the seismometers, which combines body and surface waves into one arrival. Human observed calving events are used to calibrate the seismic velocity for the method, which is then applied to other calving events from August 2014 to August 2015. From this, a catalogue of calving locations is generated, which shows that calving preferentially happens at the northern end of Helheim Glacier.