Jökull - 01.01.2010, Page 151

Paleomagnetic observations in SW- and S-Iceland
Figure 1. Index map of Iceland: the active volcanic zones (with basement outcrops of mostly less than 0.78
Ma age) are shaded. Locations of the surveys reported here are indicated, as well as some small areas where
previous paleomagnetic sampling on lava flows of less than 3 Ma age has been carried out. S = Snæfellsnes
peninsula, H = Hvalfjörður, T = Tjörnes promontory, Sk = Skaftafell area, E = Eyjafjöll, I = Ingólfsfjall, J = area
in Jökuldalur containing profiles of Watkins et al. (1975) and Udagawa et al. (1999), Þ = area in Þjórsárdalur
containing profiles of Kristjánsson et al. (1998). – Kort af Íslandi, virku gosbeltin eru skyggð. Svæði sem fjallað
er um hér og í nokkrum fyrri greinum um svipað efni eru afmörkuð lauslega.
of the lavas or of the sediments between them was
presented. Secondly, the paleomagnetic results were
not presented in detail, but merely polarity informa-
tion. Some maps of VGP positions were published
later by the group, and the present author was given a
printout of the remanence directions from all profiles.
As only two samples were collected in each lava flow,
it is necessary to re-sample the profiles of Wilson et
al. (1972) if one wishes to obtain lava-mean direction
values that can be used for studies of the geomagnetic
secular variation.
Several laboratory paleomagnetic studies have
been carried out in Iceland since the early 1970’s,
in some cases accompanied by radiometric dating.
Projects involving long composite sections of pro-
files in stratigraphic succession were reviewed by
Kristjánsson and Jónsson (2007) and Kristjánsson
(2009). One of these sections (Kristjánsson et al.,
1980) overlaps with the areas in southwest Iceland
covered by Einarsson (1957,1962). A number of other
paleomagnetic studies have been on a smaller scale.
Among them are studies on lavas mostly less than 2
Ma old, published by Watkins et al. (1975) and Uda-
gawa et al. (1999) in Jökuldalur (J), Kristjánsson et
al. (1988) in Eyjafjöll (E), Tjörnes (T) and Ingólfsfjall
(I), Eiríksson et al. (1990) in Tjörnes, Kristjánsson et
al. (1998) in Þjórsárdalur (Þ), and Helgason and Dun-
can (2001) in the Skaftafell area (Sk), see Figure 1.
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