Jökull - 01.12.1961, Side 40

hods. The tliermal methods are discussed in a
special paper by Bodvarsson and Palmason
(1961).
The application of the electric resistivity met-
hod is based on the fact that the electric resis-
tivity of rock decreases with increasing tempera-
ture and increasing degree of thermal alteration.
The mapping of the subsurface resistivitv is
therefore a quasi-quantitative method of study-
ing the subsurface temperature field. A case
history is given by Boclvarsson (1950). The main
limitation of the method is the low depth pene-
tration.
A large scale investigation of the chemical
composition of the thermal waters and gases in
Iceland has revealed the fact that the chemical
composition appears to depend on the base
temperature. This is mainlv the case for the SiO^
content of the water and the CO2 content of the
gases intermixed with the steam. Chemical com-
ponents are therefore indicative of the tempera-
ture conditions. For further information the
reader is referred to the paper by Bodvarsson
and Palmason (1961).
Modern isotope methods are interesting re-
cent newcomers to the field of natural heat
prospecting. A laboratory for the study of the
D and O18 content of natural waters in Iceland
is being erected.
REFERENCES
Banwell, C. J.: Origin and Flow of Heat.
Bulletin 123. Department Of Scientific And
Industrial Research, Wellington (1957).
Barth, T. F. W.: Volcanic Geology, Hot Springs
and Geysers of Iceland. Carnegie Institution
of Washington Publ. 587 (1950).
Bodvarsson, G.: Drilling for Heat in Iceland.
Oil and Gas Journal, 47 No. 191-199 (1949).
— Geophysical Methods in the Prospecting for
Hot Water in Iceland. (In Danish). Journal
of the Engineers’ Association in Iceland, 35.
No. 5, 49-59 (1950).
— Report on the Hengill Thermal Area. (In
Icelandic with a summary in English). Jour-
nal of the Engineers’ Association in Ice-
land, 36. No. 1, 1-48 (1951).
— Natural Heat in Iceland. Paper 197 K/8 5th
Worlcl Power Conference in Vienna (1956).
— Geothermal Effects of the Pleistocene Gla-
ciation in Iceland. Jökull, 7. 1—20 (1957).
Bodvarsson, G. ancl Palmason, G.: Exploration
of Subsurface Temperature in Iceland. Con-
ference on New Sources of Energy, Rome
(1961). Published in Jökull, No. 11, 1961.
Báth, M.: Crustal Structure of Iceland. Journal
Geoph. Research 65, No. 6. 1797-1807
(1960).
Báth, M. and Tryggvason, E.: Upper Crustal
Structure of Iceland, (In press). (1961).
Craig, H., Boato, G., and White, D. E.: Isotopic
Geochemistry of Thermal Waters. Proceed-
ings of the Second Conference on Nuclear
Processes in Geologic Settings. Publ. 400.
Natl. Academy of Sciences. Natl. Research
Council (1956).
Einarsson, T.: Ueber das Wesen der Heissen
Quellen Islands. Societas Scientarium Is-
landica, Reykjavík (1942).
Sonder, R.: Studien iiber heisse Quellen und
Tektonik in Island. Zurich (1941).
Studt, F. E.: The Wairakei Hydrothermal Field
under Exploitation, New Zealand Journal of
Geology ancl Geophysics, 1, No. 4, 707—723
(1958).
Thorkelsson, Th.: On Thermal Activity in Ice-
land, Reykjavík (1941).
Thoroddsen, Th.: Die Geschichte der isldnd-
ischen Vulkane. D. Kgl. Danske Vidensk.
Selsk. Skrifter. Naturvidenskap og Matema-
tik, Afd. 8, Raekke, IX, Copenhagen (1925).
White, D. E. and Brannock, W. W.: The Sources
of Heat and Water Supply of Thermal
Springs, with Particular Reference to Steam-
boat Springs, Nevada. Trans. Geophys.
Union, 31, 566-574 (1950).
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