Jökull - 01.12.1982, Page 17

Fig. 2. Distribution of the 1100 m erosion surface
in the Austfirðir; figures give the height above sea
level in hundreds of metres. Stippled - area of the
1 lOOmsurface. Solid black-flat-topped mountains
which are remnants of the 1100 m surface. x-sharp
peaks which rise to the levelof the 1100 m surface.
Mynd 2. Útbreiðsla 1100 m rofflatar á Austfjörðum.
Hæðir í hundruðum m.
above it, deduced from the zeolite zones, varies from
asmuch as600 m west of Hamarsfjörður to 100 mor
less at Seyðisfjörður and the Eyvindará valley area,
and averages 200 m, and the total rock eroded away
from above it is estimated to have amounted to 900
km3.
One major anomaly is the relatively low levei of
the zeolite zones in the Seyðisfjörður-Eyvindará
area. Some summits (for instance, Skagafell, Fig. 5)
rise above the zeolite zones, and lavas have empty
vesicles and despite their 9 m.y. age are as fresh as
postglacial lavas. An anomaly in the river pattern
— the Eyvindará valley system — is located here,
and the original Eyvindará probably flowed down a
depression in the upwarped surface.
The 1100 m surface may have extended beyond
the present eastern seaboardof Iceland, over partof
Fig. 3. Distribution of the 850 m erosion surface in
the Austfirðir; symbols as in Fig. 2. The cross-shad-
ed area in the southwest is an upland area mostly
between 800 and 900 m above sea level, but it is
probably not part of the 850 m surface.
Mynd 3. Útbreiðsla 850 m rofflatar á Austfjörðum.
Sömu tákn og á Mynd 2.
JÖKULL 32. ÁR 15