Jökull - 01.12.2006, Page 56

Kristjánsson et al.
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Appendix
Profile locations, tectonic tilt corrections, and geolog-
ical notes. – Staðsetningar, áætlaður halli jarðlaga og
stuttar lýsingar.
TD is on the west side of the gully Garðsgil crossing
Highway #1 in Norðurárdalur, beginning just below
the road. Coordinates: 65◦25’.78N, 19◦04’.26W. The
profile was first mapped by Á. G. and J. Helgason in
1976. Tectonic tilt decreases from 8◦ at base to 6◦ at
top, downdip 200◦E. As in the other profiles of this
project, the lavas sampled are mostly tholeiites with-
out appreciable interbasaltic sediments. The stratigra-
phy and geological setting indicates that the sequence
belongs to the lower part of the Sólheimar formation
of Hjartarson (2003).
TB: The major part of the profile lies northeast of
the gully Geldingsgil on the southeastern slopes of
Norðurárdalur. Coordinates: 65◦25’.9N, 19◦02’.1W.
Tilt decreases from 7◦ at base to 3◦ at top, downdip
200◦E. The stratigraphy of the profile as mapped by
Á. G. and J. Helgason (Saemundsson et al. 1980) has
now been slightly revised on the basis of new map-
ping by H. H. There are about 10 m of sedimentary
rocks overlying flow 62. After flow 68 the profile
moves 200 m to the east where it continues up to the
54 JÖKULL No. 56