Náttúrufræðingurinn - 1979, Qupperneq 69

HEIMILDIR
S U M M A R Y
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ing Episode in north Iceland. Nature,
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activity associated with the Septem-
ber 1977 deflation of the Kraíla
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8-11, 19-20, 22, 24, 27-29, 33. Raun-
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Kerlingarhólar, old eruptive
fissures on the Krafla fault swarm
by S. Eliasson,
Skinnastadur, 671 Kópasker, Iceland
During the last few years a rifting epi-
sode has been occurring on the 100 kilo-
meters long Krafla fault swarm in NE-
Iceland, characterized by repeated intense
earthquake swanns and ground move-
ment, together with small eruptions in
the Krafla caldera, north of Mývatn. A
probable horizontal migration of magma
from the caldera into the fault swarm has
been suggested (Björnsson et al., 1977,
Brandsdóttir et al., 1978, Einarsson, 1976
—78, Sigurðsson, 1977 etc.). The present
author investigated an old eruptive center
on this fault swarm, tlie Kerlingarhólar,
25 km north of the northern rim of the
caldera. Two short eruptive fissures, ar-
ranged en echelon, were found, having
produced fluid basaltic lava flows, with
area of ca. 12 km2. Petrological analyses,
perfornted by K. Grönvold at the Nordic
Volcanological Observatory, showed a
close resemblance to the Krafla basaltic
products. Soil profiles indicate an age of
1500—2000 yr. The Kerlingarhólar most
probably erupted in an event of magma-
tic migrntion from the Krafla caldera.
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