Jökull - 01.12.1961, Side 34

(c) The low-temperature activity.
There are approximately 250 low-temperature
thermal areas scattered over the lowlands of the
western half of the country. The number of
major springs is about 600 and the total inte-
grated flow of all hot-water springs is rougly
1.500 liters per second. The total sensible (above
4° C) Iieat output of the springs amounts to
some 108 cal/sec, giving an average temperature
of 75° C.
The low-temperature areas are in a great
number of cases distributed in a linear pattern.
This suggests a common structural control and
interrelation between the individual thermal
areas on the lines. In accordance with the dis-
cussion below, the individual lines will be re-
TABLE II
Major low-temperature thermal lines in Iceland.
Total natural Max. surface Heat
flow temp. output
liters/sec. C. magnitude
(a) 52 100 I
(b) 140 100 I
(0 60 100 I
(d) 70 100 I
(e) 120 83 I
(0 10 88 I
(g) 400 100 II
(h) 70 89 1
(i) 145 100 I
Remarks on drilling,
base temperature,
etc.
Includes the Great Geysir, borderline case.
Borderline case.
Base temp. at Reykir 98° C, 70 wells at Reykir,
max depth 1,380 meters. Output of wells
370 Iiters/sec. at 87° C.
Base temp. in Reykjavik 146° C, max. depth
2,200 meters. Output of wells 134 liters/sec at
a max. temp. 138° C.
System of lines. Includes largest hot water
spring at Deildartunga.
Borderline case.
TABLEIII
Hi^h-temperature thermal areas in Iceland.
Eleva- Heat
tion Area output
Name m km2 magnitude
I. Reykjanes . . . . 15 1 1
2. Trölladyngja . . 120 5 I
3. Krysuvik 150 10 I
4. Hengill . . 30-600 50 II
5. Kerlingafjöll . . 900 5 II
6. Torfajökull . . . 900 100 III
7. Vonarskard . . . . . 1,000 I
8. Grímsvötn .... . . 1,000 12 III
9. Kverkfjöll .... . . 1,500 10 II
10. Askja . . 1,050 I
11. Námafjall 350 2.5 II
12. Krafla 450 0.5 I
13. Theistareykir . 330 2.5 I
Remarks on drilling,
base temperature
etc.
One well 162 m deep.
15 wells, max. depth 1,200 m. Base temp.
appr. 230° C.
Base temp. ca. 230° C. Numerous shallow
wells, 8 deep wells max. depth 1,200 m.
Under the Vatnajökull ice sheet.
A few shallow wells.
32