Low-frequency seismicity at Torfajokull volcano, Iceland: detailed mapping and relation to a hypothesised cryptodome

Abstract

Torfajökull is a rhyolitic volcano with a prominent caldera and vigorous geothermal activity, located in south Iceland. We operated a 30-station network of broadband Güralp 6TD seismometers inside and around the Torfajökull caldera from mid-June until early October 2005. As a result an excellent dataset with 98.8% recovery was obtained. The main focus of the project was low-frequency earthquakes, which occur in the southern part of the caldera. Intriguing data on these events were recorded, for the first time also with stations very close to their origin. An ample dataset was gathered on high-frequency earthquakes, which occur principally in the western part of the caldera, in close connection to geothermal activity.