Náttúrufræðingurinn - 1977, Síða 61

3.70 Ma, 3.98 Ma, and 3.51 Ma, respec-
tively.
Correlation diagrams using older K/Ar
data, e.g. from Breidadalslieidi, North-
western Iceland, seem to confirm earlier
results suggesting an age of 15.89 ± 0.34
Ma which does not differ lrom the earlier
weighted ntean age of 16.0 ± 0.3 Ma and
a further confirmation of earlier results
from Gerpir, Eastern Iceland, is also
shown suggesting a regression age ol' 13.05
±0.12 Ma and 12.56 ± 0.05 Ma for rocks
150_220 m above the base of succession.
HEIMILDIR
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55