Archaeologia Islandica - 01.01.2002, Blaðsíða 66

Arni Einarsson, Oddgeir Hansson & Orri Vésteinsson
Bárðardalur, Seljadalur, Reykjadalur,
Þegjandadalur, Laxárdalur and
Reykjahverfi. The valleys are separated
by low hills lying in a N-S direction,
forming extensions of the highlands to
the south. The hills are, listed from the
west: Fljótsheiði, Narfastaðafell,
Laxárdalsheiði; which divides into two
towards the north: Múlaheiði and
Þorgerðaríjall, and finally Hvammsheiði.
Most of the hills rise only 100-300 m
above the coastal plain although single
knolls are higher (416 m). Most of the
present farms are situated along both
sides of the valleys, at the foot of the
hills. The Tjörnes area is somewhat dif-
ferent. The central highland of the penin-
sula slopes gently towards the ocean on
the west side and there is no coastal
plain. The farms are situated along the
westem margin of the peninsula. The
inhabited part is cut by several small
rivers that have eroded deep gullies.
The soil in the dry hilly part of the
study area is only about 1 m thick. As
steep slopes are uncommon the soil cover
is more or less unbroken, except for the
highest points where erosion by wind and
water has exposed the underlying
moraine. The hills are vegetated by
dwarf shrubs (Betula nana, Empetrum
sp., Vaccinium spp.) and lichens
(Cladonia and Alectoria) are prominent,
especially on the hilltops. Small bogs
occur in depressions, becoming more
extensive towards the highlands in the
south. Remains of birch Betula pubes-
cens woodlands occur in several places,
mostly in the hillslopes but generally the
study area is characterized by short vege-
tation that does not obstruct the visibility
of the earthworks.
Methods
Standard black and white aerial photo-
graphs taken on the 2nd and lOth
September 1976 were used for the study.
We used contact copies with about 60%
overlap and in the scale of 1:35,000.
Aerial photographs taken by the US Air
Force on the 24th of August 1960 were
used for comparison. The photographs
were studied stereographically by two
people simultaneously using a Wild
Aviopret (APT 2) 30-50x zoom stereo-
scope fitted with a "discussion tube"
altematively using transmitted and inci-
dent lighting. The earthworks were
traced on an overlaid transparency.
These were then reduced to the scale of
1:50,000 and traced on a map (Army
Map Service) of that scale. As the pho-
tographs were not orthophotos, this
method may have caused some bias as to
the exact location of some of the earth-
works.
Results
Altogether about 150 km of earthworks
were observed (Table 1, Figs. 3-5). By
adding the obvious gaps, where earth-
works have disappeared because of ero-
sion or construction work, the total
length of earthworks in the study area can
be estimated as having been well over
200 km.
The vast majority of the earthworks
were found in the moorland pastures, and
only a few were located on the lowland
plain. The preservation varied much
within the area but the earthworks in the
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