Fróðskaparrit - 01.01.1982, Blaðsíða 49
Some Magnetotelluric Measurements on the Faeroe Islands 57
explained as a change of composition (see fig. 6), but we do
not here attempt to make a petrological interpretation.
The effect of partial melting on the upper mantle would
reduce the resistivity level, but the high sub-moho velocity
(Bott et al. 1974) found beneath the Faeroe Islands, does not
support this possibility. Also, the presence of a low resistivity
layer at the crust-mantle boundary found beneath Iceland
(Beblo and Bjørnsson, 1979) is not observed in our measure-
ments.
The results obtained for the high frequencies suggest pore
fluids as the main factor in controlling the resistivities at the
upper crust, but the few data and the 2- and 3-dimensionality
of the crust make interpretation very doubtful.
Acknowledgment: One of the authors (PHN) wants to thank
for support by a grant from Statens Naturvidenskabelige
Forskningsrád.
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Bott, M. H. P., P. H. Nielsen, and ]. Sunderland, 1976. Converted P-waves
originating at the continental margin between the Iceland-Faeroe Ridge
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Bott, M. H. P., ]. Sunderland, P. ]. Smith, U. Casten, and S. Saxov, 1974.
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Haak, V., 1980. Relations between electrical conductivity and petrological
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