Helium in the thermal springs of Ûnartoq, South Greenland

Abstract

In South Greenland, the Ûnartoq hot springs (40°C) yield about 250 l/min. water with a salinity of 1 g/l, and 5 l/min of gas. A study of 8 samples taken over a period of 100 years shows very little chemical fluctuation. On the basis of the salt content of different types of water, there is a similarity between the hot spring waters and waters of mixed origin (meteoric and sea water). The gas content (principally N₂) also presents some analogy with that of meteoric and sea water with the exception of helium (2.25 voL % of the gases; 54 m³/yr) which gives these waters, their distinctive character. The technique of gas determination by mass spectrometry and gas chromatography is presented in some detail. The possible origin of water, gas and heat flow are briefly discussed.