Rit (Vísindafélag Íslendinga) - 01.06.1967, Blaðsíða 131

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Pálmason, G., 1963: Seismic refraction investigation of the basalt lavas in
northern and eastern Iceland. Jökull 13, 40—60.
— — 1967: Upper crustal structure in Iceland. This symposium.
Thorsteinsson, Th., 1967: Water level measurements in boreholes in
Reykjavík (in Icelandic). National Energy Authority report to the
Reykjavík Municipal District Heating Service.
Wooding R. A., 1957: Steady state free thermal convection of liquid in a
saturated permeable medium. J. Fluid Mech. 2, 273—285.
DISCUSSION
Trausti Einarsson: The high thermal gradient in the peri-
pheral lowlands of Iceland may, at least in part be due to
hydrostatic pressure, cf. the general radial ground-water cur-
rent (Trausti Einarsson 1950 and 1966, Tímarit Verkfraed-
ingafélags Islands 51, p. 23—32). The ground water circula-
tion is here due to the hydrostatic head caused by the elev-
ated central parts of the country. Such variation in hydrosta-
tic pressure is absent in a submarine ridge. But, as the author
suggests, convection in the ridge seems theoretically possible
and is an interesting suggestion.
Th. Sigurgeirsson: The geothermal area on the Reykjanes
Peninsula seems to be caused by such convection. Isotopic
composition shows that the hot water originates in the sea,
but in the hot springs the water rises up to 20 m above sea-
level.