Jökull - 01.12.1953, Page 22

Fig. 11. Rough sketcli map o£ the thermal area
in Kverkfjöll vestri. Dots: Steam vents and mud
pools. 1: The biggest steam vent (Gámur). 2:
Small steam vent with sulphur deposits. 3: The
biggest mud pool (Kraumur). 4: Hot springs
high in silica. 5: Lake. 6—8: Ice cauldrons.
liiss af jarðhitasvœðinu í Kverkfjöllum vestri.
Punktar: Gufuhverir og leirhverir. 1: Stœrsti
gufuhverinn (Gámur). 2: Gufuholur með
brennisteinsskán i kring. 3: Stœrsti leirhverinn
(Kraumur). 4: Laugar með kisilútfellingu. 5:
Jökullón. 6—8: Ketilsig i jöklinum.
vestri, is 1860 m on the map, but it is probably
near to 1900 m, and might be even greater.
Thermal activity in Kverkfjöll eystri.
When we came to the pass between the 1920
m summit and the next peak to the south of
it early on the night of 4 July, we observed
that some steam was issuing from small spots
on the nearly precipitous E slope of the Kverk-
fjöll ridge some 15 m beneath the col, or in ab.
1880 m hight. The Swede Söderin was lowered
down on a rope to measure the temperature in
the steam holes, the highest temperature found
was 84°C. The steam did not smell of sulphur,
but the tuff around the holes had a reddish
colour.
Ascending the 1920 m summit, we found on
the ridge S of the cairn warm exhalations from
several spots, temp. ab. 20°C, and in the firn
around the snowbare ridge there were several
holes melted by thermal exhalations and such
holes were also found along the peak next to
the south. These two peaks are surely by far
the highest places where thermal activity has
been found in Iceland. On 6 Aug. 1933, P.
Hannesson and S. Sigurðsson ascended the 1920
m summit in clear but cold weather (Hannes-
son, 1953). Hannesson feels pretty certain that
they would have observed the thermal activity
on the summit, had there been any at that time
(pers. inform.). On 13 Aug. 1946 the summit
was again ascended by the members of the
Vatnajökull expedition. We did not observe
any thermal activity either, but we stayed there
only about 10 minutes in bright sunshine on
a hot day and might have overlooked it. It is
possible, however, that the thermal activity
there has started or increased quite recently.
On the 1920 m peak we found a green moss-
covered spot, in all probability the highest
situated of its kind in Iceland.
Thermal activity in Kverkfjöll vestri.
This area was visited by Olafur Jónsson 1941
and 1946 (Jónsson 1945, 1953), and by the
Vatnajökull expedition 1946, but none of these
visits was long enough for any detailed investiga-
tion, nor was our visit 1953 long enough for
such investigations.
Fig. 11 is a very rough sketch map of this
thermal area which is mostly limited to the
slopes and bottom of a narrow valley running
from SW to NE through Ivverkfjöll vestri (cf.
Thorarinsson, 1950). The bottom of the valley
is in ab. 1600 m height. The thermal area is
crowded with acid steam vents and mud pools
and in one place on the valley bottom ara situa-
ted hot springs (4 on the sketch mapj high
in silica, forming nice silica sinter terraces
which were visible when we were there in
1946, but hacl now been submerged by the rising
lake. The biggest steam vent (1 on the map), is
in the valley bottom where it is at its narrow-
est and is not inferior in size to any steam
vent in the country except Austurengjahver in
Krísuvík. This steam vent I named Gámur. The
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