Greinar (Vísindafélag Íslendinga) - 01.01.1976, Síða 13

11
layer 3 are 1 km and 2 km respectively. VED-1 and HED-1 are
m the Tertiary basalt zones in Eastern and Westem Iceland. Depth
to layer 3 is aroimd 3.5 km at the eastem site and probably around
4-6 km on the Vestfirdir peninsula. Site DDE-2 is on Mosfellsheidi
in the Quaternary zone with depth to layer 3 around 2 km and
finally the sites HUD-1 and HUD-2 are in the Audkúluheidi region,
where the active zone is expected to have been situated 4 million
years ago.
3. PRESENTATION OF THE RESULTS
Both the electrical sounding curves, obtained near Tertiary and
Quaternary central volcanoes in Vatnsdalur and on Kjalames where
layer 3 is close to the surface, are shown on Figure 2. The resistivity
structure with depth is obtained by comparing the field-curves
with master-curves from Orellana and Mooney (9). At both places,
which are around 150 km apart, the resistivity increases in layer 3
to the same value of about 300 fim. At greater depth the data is
scattered, probably because of lateral inhomogeneity in the central
volcanoes, but 300 fim seems to be a fair estimate of the mean
10 20 40 100 200
1000 2000 4000 10000

1000-
- 600-
400-
1 XXX K-2 Kiolornes Dipole - Schlumberger - sounding
* * • HU S-2 VQ © ® © HU D-3 vo nsdalur xxxXx * X> X x ® ® « ’ ® 9 ® O ®
X X X X m m rn •••'” **/. • • •S 1 1 1 1 1 1
Kjalarnes ~50flm 200 ílm 300 fl m
Vatnsdalur ~50ftm 15 300 ftm
600
400
Depth [mj
Fig. 2: Dipole- and Schlumberger — sounding in eroded central volcanoes,
Kjalames and Vatnsdalur.