New mass increase beneath Askja volcano, Iceland – a precursor to renewed activity?
Article first published online: 24 MAY 2010
© 2010 Blackwell Publishing Ltd
Volume 22, Issue 4, pages 309–313, August 2010
How to Cite
Rymer, H., Locke, C., Ófeigsson, B. G., Einarsson, P. and Sturkell, E. (2010), New mass increase beneath Askja volcano, Iceland – a precursor to renewed activity?. Terra Nova, 22: 309–313. doi: 10.1111/j.1365-3121.2010.00948.x
- Issue published online: 8 JUL 2010
- Article first published online: 24 MAY 2010
- Received 25 November 2009; revised version accepted 23 April 2010
Terra Nova, 22, 309–313, 2010
Askja is an active central volcano located on the NS trending en echelon rift zone marking the mid-Atlantic plate boundary in North Iceland. Between 2007 and 2009, we observed a gravity increase at the centre of the caldera. This contrasts with net gravity decreases recorded between 1988 and 2007 interpreted previously in terms of magma drainage. The recent gravity increase is rapid, but similar in terms of lateral extent to the preceding decrease. This gravity increase corresponds to a sub-surface mass increase of 0.68 × 1011 kg at about 3 km depth. It is possible that the new gravity increases observed at Askja reflect accumulation of magma beneath the caldera and thus may herald a new phase in the activity of this volcano, which last erupted in 1961.