Jökull - 01.12.1987, Page 12

indicate a relatively primitive undegassed mantle source
and have been correlated with the presumed mantle
plume under the SE-part of central Iceland.
Anomalous concentrations of mercury in soil and of
radon in soil air in the Hrafntinnusker area reflect sub-
surface permeability anomalies controlling upflow of
geothermal steam. The anomalies form distinct linear
patterns striking NE-SW and NW-SE. The former direc-
tion is parallel with the present day tectonic fabric, but
the latter with an earlier tectonic fabric.
REFEREN CES
Árnason, B. 1977: Groundwater Systems in Iceland Traced by
Deuterium. Publ. Societas Scientarum Islandica, Reykjavík
236 pp.
Arnórsson, S. 1969: A Geochemical Study of Selected Elements
in Thermal Waters of Iceland. Unpubl. Ph.D. thesis, Univ.
London, England, 353 pp.
Arnórsson, S. 1984: Germanium in Icelandic geothermal sys-
tems. Geochim. Cosmochim. Acta 48: 2489-2502.
Arnórsson, S. 1985: The use of mixing models and chemical
geothermometers for estimating underground temperatures
in geothermal systems. J. Volc. Geothermal Res. 23: 299-
335.
Arnórsson, S. 1987: Gas chemistry of the Krísuvík geothermal
field, SW-Iceland with special reference to evaluation of
steam condensation in the upflow zones. Jökull, this issue.
Arnórsson, S. and E. Gunnlaugsson 1985: New gas geother-
mometers for geothermal exploration: Calibration and appli-
cation. Geochim. Cosmochim. Acta 49: 1307-1325.
Arnórsson, S. and G. ívarsson 1985: Molybdenum in Icelandic
geothermal waters. Contrib. Mineral. Petrol. 90: 179-189.
Arnórsson, S., E. Gunnlaugsson and H. Svavarsson 1983: The
chemistry of geothermal waters in Iceland II. Mineral equilib-
ria and independent variables controlling water composi-
tions. Geochim. Cosmochim. Acta 47: 547-566.
Bödvarsson, G. 1961: Physical characteristics of natural heat
resources in Iceland. Jökull 11: 29-38.
Condomines, H., K. Grönvold, P. J. Hooker, K. Muhlenbachs,
R. K. O'Nions, N. Óskarsson and E. R. Oxburgh 1983: Heli-
um, oxygen, strontium and neodynium isotope relationships
in Icelandic volcanics. Earth Planet. Sci. Letters 66:125-136.
D’Amore, F. and C. Panichi 1980: Evaluation of deep temper-
atures in hydrothermal systems by a new gas geothermom-
eter. Geochim. Cosmochim. Acta 44: 549-556.
Gudmundsson, J. S. 1983: Geothermal electric power in Ice-
land: Development in perspective. Energy 8: 491-513.
ívarsson, G., K. Sœmundsson and 5. Arnórsson 1987: The Tor-
fajökull silicic central volcano, South Iceland: Stratigraphy,
structural geology and rock geochemistry. Jökull, this issue.
Kononov, V. /., B. A. Mamyrin, B. G. Polak&ná L. V. Khaba-
rih 1974: Helium isotopes in the thermal waters of Iceland.
Dokl. Akad. Nauk. SSSR. 217: 172-175.
Kurz, M. D., P. S. Meyer and H. Sigurdsson 1985: Helium
isotope systematics within the neovolcanic zones in Iceland.
Earth Planet. Sci. Letters 74: 291-305.
Óskarsson, N., G. E. Sigvaldason and S. Steinthórsson 1982: A
dynamic model of rift zone petrogenesis and the regional
petrology of Iceland. J. Petrol. 23: 28-74.
Óskarsson, N., S. Steinthórsson, and G. E. Sigvaldason 1985:
Icelandic geochemical anomaly: origin, volcanotectonics,
chemical fractionation and isotopic evolution of the crust. J.
Geophys. Res. 90: 10,011-10,025.
Pálmason, G. 1980: Geothermal energy. Náttúrufrædingurinn
50: 147-156 (Inlcelandic).
Pálmason, G. and K. Sœmundsson 1974: Iceland in relation to
the Mid-Atlantic Ridge. Ann. Rev. Earth Planet. Sci. 2:
25-50.
Pálmason, G., J. D. Friedman, R. S. Williams Jr., J. Jónsson
and K. Sæmundsson 1970: Aerial infrared surveys of Reyk-
janes and Torfajökull thermal areas, Iceland, with a section
on cost of exploration surveys. Geothermics 2,1: 399-412.
Poreda, R., J. Welhan, H. Craig and S. Arnórsson 1984: Helium
isotopes and mantle methane in Icelandic geothermal fluids
and volcanic rocks. EOS 65(no. 45): 1152.
Sigvaldson, G. E. 1959: Mineralogische Untersuchungen iiber
Gesteinszersetzung durch postvulkanische Aktivitat in Is-
land. Contrib. Mineral. Petrol. 6: 405-426.
Sigvaldason, G. E. and N. Óskarsson 1976: Chlorine in basalts
from Iceland. Geochim. Cosmochim. Acta 40: 777-789.
Sœmundsson, K. 1972: Notes on the geology of the Torfajökull
central volcano. Náttúrufrædingurinn 42: 81-99 (In Icelan-
dic).
Varencamp, J. C. and R. P. Buseck 1983: Hg anomalies in soils:
A geochemical exploration method for geothermal areas.
Geothermics 12: 29-47.
Walker, G. P. L. 1974: Eruptive mechanisms in Iceland. In: L.
Kristjánsson (Ed.). Geodynamics of Iceland and the North
Atlantic Area. Reidel, Dordrecht, Holland, 189-202.
Whitehead, N. E. 1984: Geothermal prospecting by ground ra-
don measurements. J. Volc. Geothermal Res. 20: 213-229.
10