Rit (Vísindafélag Íslendinga) - 01.06.1967, Qupperneq 206

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There are certainly such problems. The fissure systems of
the median zone of Iceland are probably more accessible for
detailed studies than these of any other part of the World Rift
System, this, among other things, because of the nakedness of
the country, which greatly facilitates the use of aerial photo-
graphs. One of our aims should be to map the entire fissure
system of the median zone and also to make a tectonic map
of the entire country. The symposium has revealed how in-
sufficient our knowledge is of the tectonics in some parts
of the country, especially the Vestfirdir area. We need a de-
tailed map of dykes and dyke swarms, combined with mag-
netic studies. Continued aeromagnetic survey of Iceland
might help to interprete the results of similar measurements
on the submarine parts of the ridges.
In his lecture, G. Kjartansson stressed an important fact
which I also pointed out in my lecture at the Ottawa sympo-
sium on the World Rift System in 1965 namely — to quote
myself, that “the median zone is not only a supramarine part
of the Mid-Atlantic rift zone, it is also an area where rela-
tively recent volcanism has taken place under conditions
rather similar to those along the submarine parts of the
ridge”. The magma extruded is in both cases to a great ex-
tent very similar. Consequently every explanation of the topo-
graphy of the Icelandic móberg areas, such as the explana-
tion presented by Kjartansson, has a bearing on the topo-
graphy of the submarine ridges, which greatly adds to its
importance. Dredging and underwater photographing on the
mid-ocean ridges have revealed how important role pillow
lavas play in their building up, and I may also mention that
detailed study of a limited area of the Mid-Atlantic Ridge
between 45°N and 46°N has recently led R. D. Loncarevic
and his collaborators to the conclusion that its main features
are volcanic rather than tectonic although the mechanism of
the formation of the median valley itself is still obscure.
Rut for obvious reasons the submarine parts of the ridges are
much less accessible for detailed studies than the móberg