Náttúrufræðingurinn - 1983, Page 46

Submarine eruption off the
Vestmannaeyjar Islands in
1637-38
by
Haukur Jóhannesson,
Icelandic Museum of Natural History,
P. O. Box 5320,
Reykjavík.
Two eruptions have occurred in the
Vestmannaeyjar volcanic system in this
century, the Surtsey eruption 1963—67 and
the Heimaey eruption 1973. A minor erup-
tion took place somewhere southwest of
Heimaey island in 1896 (Pórarinsson,
1965). In this short paper, evidence for the
fourth eruption is presented.
Two contemporaneous literary sources
mention phenomena which undoubtedly
were caused by submarine eruption in the
Vestmannaeyjar archipelago.
Sjávarborgarannáll (Markússon 1940-
48), which is partly based on a lost annals,
Grindavíkurannáll, reports that people in
the Landeyjar district in South Iceland
(Fig. 1) had often in October and Novem-
ber of 1637 seen flames in the sea, in
evenings and at nights in clear weather.
Further, many people in South Iceland
saw very red sky both in evenings and in
mornings at the same time.
Gísli Oddsson (1917), bishop at
Skálholt, wrote a booklet, De Mirabilibus
Islandiae, in late April 1638. There he
describes fire flames from the sea, which
were seen towards the south from
Skálholt, earlier that year.
It is firmly suggested that the phe-
nomena described in the above-mentioned
chronicles were caused by a submarine
eruption off the south coast. The Vestman-
naeyjar system is the only active volcanic
region off the south coast (see Jakobsson
1979). Comparison with descriptions of
the 1896 eruption suggests that the erup-
tion site may have been southwest of the
Heimaey island.
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