Jökull - 01.12.1989, Síða 19

have been substantial. It is suggested that the
observed drop in heat flux from the area in recent
years can be explained by the decrease in vol-
canic activity since 1940. The heat stored in lava
flows and shallow intrusions is now exhausted.
ACKNOWLEDGEMENTS
The project was supported by a grant from the
Icelandic Science Fund. The National Energy
Authority (Orkustofnun) and The Science Institute
(Raunvísindastofnun), University of Iceland gave
valuable support in supplying manpower and equip-
ment while out in the field. Especially the author is
indebted to Jósef Hólmjám, Orkustofnun, for his
participation and Dr. Helgi Björnsson for his con-
tinuing support. The Icelandic Public Road
Administration supplied explosives. The author
acknowledges the receipt of a Foreign and Com-
monwealth Office Scholarship (FCO) and an Over-
seas Research Student Scholarship (ORS) while
studying at UCL. The author would like to thank his
supervisor, Dr. John Milsom, for his support as well
as critical and constructive comments on drafts of
this paper. Professor Sveinbjörn Björnsson, Karl
Gunnarsson and Dr. Ólafur Flóvenz read the
manuscript and suggested several improvements of
the paper.
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