Report on Krafla (Iceland) — March 1981
Scientific Event Alert Network Bulletin, vol. 6, no. 3 (March 1981)
Managing Editor: Lindsay McClelland.
Krafla (Iceland) Inflation reaches level at which previous eruptions were triggered
Please cite this report as:
Global Volcanism Program, 1981. Report on Krafla (Iceland). In: McClelland, L (ed.), Scientific Event Alert Network Bulletin, 6:3. Smithsonian Institution. https://doi.org/10.5479/si.GVP.SEAN198103-373080.
65.715°N, 16.728°W; summit elev. 800 m
All times are local (unless otherwise noted)
"As of 2 April, land elevation over the Krafla magma reservoirs, as indicated by tiltmeters, was about the same as at the time of the eruption that began 30 January. Inflation continued and from past experience an eruption can be expected to take place in the near future, possibly within the next few weeks."
Geologic Background. The Krafla central volcano, located NE of Myvatn lake, is a topographically indistinct 10-km-wide caldera that is cut by a N-S-trending fissure system. Eruption of a rhyolitic welded tuff about 100,000 years ago was associated with formation of the caldera. Krafla has been the source of many rifting and eruptive events during the Holocene, including two in historical time, during 1724-29 and 1975-84. The prominent Hverfjall and Ludent tuff rings east of Myvatn were erupted along the 100-km-long fissure system, which extends as far as the north coast of Iceland. Iceland's renowned Myvatn lake formed during the eruption of the older Laxarhraun lava flow from the Ketildyngja shield volcano of the Fremrinamur volcanic system about 3800 years before present (BP); its present shape is constrained by the roughly 2000 years BP younger Laxarhraun lava flow from the Krafla volcanic system. The abundant pseudocraters that form a prominent part of the Myvatn landscape were created when the younger Laxarhraun lava flow entered the lake.
Information Contacts: K. Grönvold, NVI.