Náttúrufræðingurinn - 1979, Page 69

HEIMILDIR
S U M M A R Y
Björnsson, Axel o. fl., 1977. Current Rift-
ing Episode in north Iceland. Nature,
Vol. 266.
Brandsdóttir, Bryndis o.fl., 1978. Seismic
activity associated with the Septem-
ber 1977 deflation of the Kraíla
central volcano in NE-Iceland. Raun-
vísindastofnun, Reykjavík.
Einarsson, Páll, 1976—78. Skjálftabréf nr.
8-11, 19-20, 22, 24, 27-29, 33. Raun-
vísindastofnun liáskólans og Veður-
stofa íslands. Reykjavík.
Eliasson, Sigurvin, 1977. Molar um Jök-
ulsárhlaup og Ásbyrgi. Náttúrufr., 47,
3.-4. hefti, Reykjavík.
Grönvold, Karl o.fl., 1978. Skjálftabréf
nr. 32, 35. Raunvísindastofnun og
Veðurstofan.
Kjartansson, Guðmundur, 1949. Náttúru-
fræðingurinn, 19: 3—4.
Sigurðsson, Oddur, 1977. Náttúruhamfar-
ir í Þingeyjarþingi (II), 1976—78.
Týli, 7., 2. liefti, Akureyri.
Sœmundsson, Kristján, 1977. Jarðfræði-
kort af íslandi, blað 7, Norðaustur-
land. Landmælingar íslands og Nátt-
úrufræðistofnun Islands. Reykjavík.
— Óbirt hraunakort af Kelduhverfi
(Mælikv. 1:50000).
Þórarinsson, Sigurður, 1962. The Post-
glacial History of the Mývatn Area
and the Area between Mývatn and
Jökulsá á Fjöllum. On the Geology
and Geophysics of Iceland. Copen-
hagen.
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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