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SUMMARY
Volcanic eruptions in historical
time on the Reykjanes
peninsula, South-West Iceland
by
Jón Jónsson,
Department of Natural Heat,
National Energy Authority,
Grensásvegur 9,
108 Reykjavík.
The Reykjanes peninsula is a supramar-
ine part of the Mid-Atlantic Ridge, and
the south-westernmost part of the active
volcanic zone of Iceland lies along it. Dur-
ing the last few years the peninsula has
been geologically ntapped on the scale
1:25.000, with emphasis on geothermal
activity, postglacial volcanic activity and
dating of eruptions.
The postglacial lavas of the Reykjanes
peninsula cover an area of 1064 knr, or
52% of the peninsula, and their volume is
at least 42 km’. Historical lavaflows cover
143 krn2 and their volume is approximately
2.3 km'. These figures are considered to be
a minimum.
For age determinations four different
methods have been applied Cf. Table I:
1) Historical rocords (S).
2) C1J age determinations (C1J).
3) Tephrochronological methods (T).
4) Relation to lava flows with known
age (R).
Using these methods it has been possi-
ble to ascertain 12 or 13 eruptions which
have occured in historical times.