Fróðskaparrit - 01.01.1982, Blaðsíða 48
56 Some Magnetotelluric Measurements on the Faeroe Islands
1727 1156 638 636 C96 39t 315 253 203
Electrical conductivity of ultramafic material. A prominent feature of this
material is the steep rise of the conductivity function with ‘activation
energies’ between 2 and 4 eV, a somewhat enigmatic result (c.f. text.)
(1), (2), (5), (6), (7), (9), (16), (18), (21) eclogites (Lastovickova, 1976);
(3), (11) peridotites; (4) dimites; (10), (12) olivinites (Dvorák, 1973); (13)
olivinite + peridotite (Bondarenko and Fel’dmann, 1973); (14), (15)
peridotite (Parkhomenko, from Bondarenko and Fel’dmann, 1973) +
plagioclase peridotite (Bondarenko and Fel’dmann, 1973); (17) dunite
(Bondarenko and Fel’dmann, 1973); (19) pyrope spinel dunite; (20) pyrope
peridotite (Bondarenko and Fel’dmann, 1973); (22) garnet websterite; (24)
spinel lherzolite; (25) garnet peridotite; (26) garnet lherzolite; (27) garnet
peridotite; (28) eclogite (Rai and Maghnani, 1978b).
Fig. 6. The figure is taken from V. Haak (1980).
distort the transfer functions corresponding to larger depths.
We should, therefore, be cautious in putting too much quanti-
tative emphasis on the geological interpretation of our data,
and hence the apparent increase in resistivity with depth could
well be an artifact.
If, on the other hand, the observed increase of resistivity
reflects the true situation in the upper mantle, this could be