Jökull - 01.12.1992, Page 24

ment/basalt interface are analogous to typical up-
per crustal P-velocities in Iceland. A velocity
of 6.8 km/s at a depth of 5-6.5 km best fits the
data, which indicates that the deepest traveling
rays sample the uppermost part of Layer 3.
ACKNOWLEDGMENTS
The fieldwork was carried out by Barði Þorkels-
son, Bryndís Brandsdóttir, Erik Sturkell, Gunnar
Guðmundsson, Hajime Shiobara, Hideki Shima-
mura, Jósep Hólmjárn, Kristján Jónasson, Masashi
Mochizuki, Ragnar Stefánsson, and the ship crew of
M/V Týr of the Icelandic Coast Guard. We thank
the families at Núpskatla, Leirhöfn, Núpur, Gilhagi,
Astjörn, Máná, Reynihlíð and Argerði for their aid
and hospitality during the fieldwork. This research
was supported by the Japan and Icelandic National
Science Foundations and Icelandic Coast Guard. Re-
views by Ágúst Guðmundsson, Freysteinn Sigmunds-
son, Karl Gunnarsson, and Páll Einarsson improved
the manuscript.
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22 JÖKULL, No. 42, 1992