Jökull - 01.12.1981, Page 10

Authority of Iceland, and from Karl Grönmld who
provided the microprobe analyses at the Nordic Vol-
canological Institute, Reykjavík, as well as their
interest and time. Sveinn Jakobsson at the Museum of
Natural History, Reykjavik has also been of great
help in providing thin sections and microscope facili-
ties. Financial support was provided by NA TO Re-
search Grant No. 1629.
Brian Whalley and Jim McGreevy of the Queen’s
University, Belfasl have assisted in laboralory work
and have discussed the problem at length. Jim Mc-
Greevy is thanked for making the electron micrograph
in Fig. 3. Leó Kristjánsson and Stefán Arnórsson
critically read the paper.
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