Subgacial Eruption in Vatnajökull
On September 29, 1996 at 10:48 an earthquake of magnitude 5 on the Richter
scale was detected within the Vatnajökull icecap in SE Iceland. This
event was followed by an intense earthquake swarm with a large number of
small events with intermittent larger quakes of magnitude 3-4 on the Richter
scale. The activity continued at similar level until shortly before midnight
on September 30th when volcanic tremor was recorded and earthquake shocks
became less frequent. In the afternoon of September 29 a warning was issued
to national and international aviation authorities that an explosive
(phreatic) eruption might be expected within the near future and an ash
cloud might interfere with the dense air traffic across the Atlantic.
Iceland -- 1996
In the morning of October 1st an over flight discovered a subsidence bowl in
the glacier surface at a location where an eruption had occurred in 1938.
More or less continuous over flights during the day observed continuous
increase in the size and depth of the initial subsidence bowl as three
additional bowls formed on a line N30E indicating intensive melting at the
base of the glacier along a fissure 5-6 km long.
Simultaneously the ice cover on the 10 km diameter Grímsvotn caldera
some 15 km to the south of the active subglacial fissure started to rise
indicating that melt water from the eruption was flowing into the caldera
depression and lifting its ice cover.
This text describes the beginning of a violent process of eruptions, leading
eventually to a partial meltdown of the glacier.
The above citation is the top part of an introductory file
originally to be found at the website of the
Volcanological Institute of
Iceland. The page has gone from that website, it seems, but it
still is available
at the website of the
of Michigan mirror.
A personal account of the eruption is provided by the
Eruption Filming Diary by filmmaker Villi Knudsen
-- sadly this page and Knudsen's Volcano Show seem to have
vanished from the Web.
I have collected a number of images about the eruption from the Internet
and I kept them because I like them, and therefore I can also make them
available to others, hence this page.
To reduce loading time, I've put the images on four pages (each page is of
the other of 40 kb); the pictures on this page are just an example.
The file size in bytes follows the name of the file.
(The images are given in a rather arbitrary order.)
I'm afraid that only some of the pictures have a caption; if you
want to know more visit the above mentioned sites.
Page 1, example:
Page 2, example:
Page 3, example:
Page 4, example:
The source of the images is mainly
Volcanic Eruption under Vatnajökull [page has gone].
Some of image came from the
site of the Volcanological Institute
of Iceland, the
site of an air company
[page has gone] and the
site of Magnus M. Halldorsson.
These pages provide links to more sites with images and info.
For any questions regarding ownership and rights of these pictures, you
have to consult the Web sites listed.
<=== main page of pictures found on Internet
Jos van Geffen --
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created: 7 November 1996
last modified: 14 June 2011