Vatnafjöll

Iceland

Highest pointElevation1,235 m (4,052 ft)Coordinates63°55′12″N 19°40′12″W / 63.92000°N 19.67000°W / 63.92000; -19.67000GeographyLocationIcelandGeologyAge of rockTephrochronologyMountain typeFissure vents of HeklaLast eruption1200 years ago

Vatnafjöll (Icelandic pronunciation: [ˈvahtnaˌfjœtl̥] ^ⓘ) is a 40 km (25 mi) long, 9 km (6 mi) wide basaltic fissure vent system that is south-east of Hekla, Iceland. It includes from the north towards the south the hills of Innri-Vatnafjöll at 1,089 m (3,573 ft) high, Fremri-Vatnafjöll at 901 m (2,956 ft) and Vatnafjallarani at 574 m (1,883 ft) as the main Vatnafjöll edifice,^[1] at a distance of about 7 km (4.3 mi) from Hekla.^[2]^: 1151 It is part of the same system as Hekla,^[3] and the term Hekla-Vatnafjöll volcanic system has been used to describe it.^[4] More than two dozen eruptions have occurred at Vatnafjöll during the Holocene Epoch. Vatnafjöll has not erupted during the last 1100 years.^[5]^: 4313 While these eruptions were predominantly effusive some basaltic tephra deposits have been found up to 40–50 km (25–31 mi) away.^[6]

A M_w5.9 with an epicenter near the main Vatnafjöll edifice occurred on 25th May, 1987,^[5]^: 4313 where the transform South Iceland seismic zone meets the East volcanic zone of Iceland. Later analysis has suggested that initiation was from strain relief but a subsurface dyke intrusion then occurred over the next 3 days.^[2]^: 1161

References

^ "National Land Survey of Iceland (Kortasja)". Retrieved 3 July 2024.
^ ^a ^b Ágústsson, K.; Linde, A.T.; Stefánsson, R.; Sacks, S. (1999). "Strain changes for the 1987 Vatnafjöll earthquake in south Iceland and possible magmatic triggering". Journal of Geophysical Research: Solid Earth. 104 (B1): 1151–1161. Bibcode:1999JGR...104.1151A. doi:10.1029/1998JB900027.
^ "Hekla". Global Volcanism Program. Smithsonian Institution. Retrieved 3 July 2024.
^ "Catalogue of Icelandic Volcanoes:Catalogue of Icelandic Volcanoes:Hekla". Retrieved 3 July 2024.
^ ^a ^b Bjarnason, I.T.; Einarsson, P. (1991). "Source mechanism of the 1987 Vatnafjöll earthquake in South Iceland". Journal of Geophysical Research: Solid Earth. 96 (B3): 4313–4324. Bibcode:1991JGR....96.4313B. doi:10.1029/90JB00831. hdl:20.500.11815/1036.
^ "Catalogue of Icelandic Volcanoes:Catalogue of Icelandic Volcanoes:Hekla". Retrieved 3 July 2024.^{: Detailed Description:Eruption history and pattern:Fissure swarm}