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SUMMARY
On the age of the Svínahraun
lava flow
by Jón Jónsson
National Energy Authority, Reykjavik
The Kristnisaga, written in the 12th
century, describes the event when Iceland
was converted to Christianity by a deci-
sion of the Alþing (Parliament) in the
sunnner AD 1000. A reference is made to
a volcanic eruption in the mountains of
the Ölfus district SW-Iceland, the first
volcanic activity to be mentioned in Ice-
landic literature. For at least two centuries
is lias been considered that the site of
this eruption was an eruptive fissure on
Hellisheiði. A Cu age determination in-
dicates, however, that the age of this flow
is 1855 ±65 years (Jónsson 1975). It has
now been found that the Svínahraun lava
flow (see map) is superimposed on a layer
of light tephra which was deposited about
AD 900 (Thorarinsson 1967, Jónsson
1971). Accordingly it is concluded that
the Svínahraun lava flow derives from
the eruption mentioned in the Kristni-
saga.
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