Last updated
Iceland relief map.jpg
Red triangle with thick white border.svg
Highest point
Listing List of volcanoes in Iceland
Coordinates 64°12′4″N17°0′17″W / 64.20111°N 17.00472°W / 64.20111; -17.00472
Mountain type Subglacial volcano
Last eruption 1910

Thordarhyrna (Icelandic : Þórðarhyrna [ˈθourðarˌhɪ(r)tna] ) is one of seven [1] subglacial volcanoes beneath the Vatnajokull glacier in Iceland.



It last erupted in 1910 and prior to that in 1903. [2] [3]

An eruption in 3550 BC ± 500 years poured out 150,000,000 cubic meters of lava in the area of Bergvatnsárhraun, to the south of Thordarhyrna. [4]

An eruption between 1887 and 1889 had a VEI of 2. [5]


There is a mechanical interaction between Thordarhyrna and Grimsvötn, despite these volcanoes being relatively far apart, [6] so the eruption in 1902 - 1904 was combined with an eruption from Grimsvötn and had a Volcanic Explosivity Index (VEI) of 4. [7]

A fault runs (N.35°W) from Thordarhyrna towards Hamarinn, and separates two different tectonic regions. [8]

See also

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  1. "Archived copy" (PDF). Archived from the original (PDF) on 2012-03-09. Retrieved 2011-05-24.{{cite web}}: CS1 maint: archived copy as title (link) Figure 2.8 shows 7 volcanoes beneath the glacier
  2. "Eruptions in Iceland during the 20th and the 21st centuries". Archived from the original on 2012-12-21. Retrieved 2011-05-24. Eruptions in Iceland since 1900
  3. "Eruptions beneath Vatnajökull". Archived from the original on 2011-05-27. Retrieved 2011-05-27.
  6. Andrew, Ruth E. B. (20 November 2008). "Elsevier". Journal of Volcanology and Geothermal Research. Volcanic Flows and Falls. 177 (4): 1045–1054. doi:10.1016/j.jvolgeores.2008.07.025.
  8. Surface and bedrock topography mapped by radio echo sounding