most active volcanoes.
Earthquake activity in the vicinity of Hekla is usually quite low, but seems to
increase abruptly before an eruption. Before the eruption in Hekla in
2000,
increased earthquake activity was measured in the area and a seismic swarm
occurred just about an hour before the eruption. In addition to the earthquake
activity, there were some significant changes in nearby strain
/volcanoes/volcanic-hazards/earthquakes/