Jökull - 01.12.1977, Qupperneq 71

recent volcanism at Leirhnjúkur antl following
earthquake activity are of local character. Gravi-
ty changes generally reach the order of 0.1 mgai,
only near Krafla changes of a few tenths of
mgal have been found. Tlie gravity increase at
Námaskard shows a significant correlation with
lreight decrease.
ACKNOWLEDGEMENTS
The anthors thank the National Research
Council of Iceland for the permission to carry
out the gravity sarvey in Iceland. For valuable
assistance and fruitful discussions they are grate-
ful to Dr. Gudmundur Pálmason, Reykjavik.
Sincere thanks are due to the Geodetic Insti-
tute, Technical University Berlin (Profs. Dr.-
Ing. S. Heitz, Dr.-Ing. K. Marzahn) for lending
the LCR-gravity meter no. 85. Calculations have
been carried out with the CDC 73/76 of the
Regional Computing Centre of Lower Saxony.
The authors are very grateful to the German
Research Society (Deutsche Forschungsgemein-
schaft), which generously sponsored the invest-
igations.
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