The ultra-slow Gakkel Ridge is the lowest spreading velocity end member of theglobal mid-ocean ridge system. Still it hosts a number of active vents and volcanoes.During 1999 one submarine volcanic complex at around 85 N, 85 E was home to aseries of earthquakes above magnitude 4 which to this day is the best example of aglobally recorded swarm at a volcano with more than 200 events registered in the ISCbulletins. In order to better constrain the locations and mechanisms of these events wecross-correlated all of them and introduced inter-event delay times for similar eventswhich were used to update the existing bulletins. Similar waveforms were only foundclose (i.e. < 3000 km) to the source and vary from station to station. Only 3 eventsare similar at more than 4 stations at the same time. Using modern global hypocenterlocation algorithms such as HYPOCENTER from SEISAN, HYPOSAT and NON-LINLOC we limited the lateral extent of the swarm, its depth and associated deptherrors by varying the velocity model. Most of the events seem to be focussed between0 and 30 km depth and ascent paths of seismicity and thus maybe magmatic dykesappear to be traceable.
AWI Organizations > Geosciences > Junior Research Group: MOVE
Helmholtz Research Programs > PACES I (2009-2013) > TOPIC 3: Lessons from the Past > WP 3.2: Tectonic, Climate and Biosphere Development from Greenhouse to Icehouse