Shallow geothermal and deep seismicity beneath Peistareykir, NE-Iceland

The seismicity in the central Þeistareykir volcanic system, NE Iceland, between 2009-2012 consists of spatially clustered earthquakes at 2-5 km depth (b.s.l.) southwest of the main geothermal fields. Deep earthquakes are located in a scattered pattern southeast of Þeistareykir at 8-20 km depth (b.s.l.). Although not associated with detectable surface uplift they may be caused by high strain rates within the plastic regime of the crust in the vicinity of the Húsavík-Flatey transform fault system or due to reduced normal friction caused by melt movements at depth.