O, H and C isotopic systematics of Icelandic groundwater

Stable water isotopes of oxygen and hydrogen have been studied in Icelandic natural waters since 1960 for hydrological and geothermal research. All the waters are of meteoric and seawater origin. The measured range in δD and δ18O is large -131 to +3.3‰ and -20.8 to +2.3‰ respectively. Some of the wa...

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Bibliographic Details
Published in:E3S Web of Conferences
Main Authors: Sveinbjörnsdóttir Arny E., Stefánsson Andri, Heinemeier Jan
Format: Article in Journal/Newspaper
Language:English
French
Published: EDP Sciences 2019
Subjects:
Online Access:https://doi.org/10.1051/e3sconf/20199807031
https://doaj.org/article/bcd1a95984d64c78bc0a1ca115c3f461
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Summary:Stable water isotopes of oxygen and hydrogen have been studied in Icelandic natural waters since 1960 for hydrological and geothermal research. All the waters are of meteoric and seawater origin. The measured range in δD and δ18O is large -131 to +3.3‰ and -20.8 to +2.3‰ respectively. Some of the waters are more depleted than any present-day precipitation suggesting a pre-Holocene component in the groundwater. Carbon isotopes of streams, rivers, soil and groundwater have been studied since 1990 in order to evaluate the carbon sources and reactions that possibly influence the carbon systematics of the water. Results show large range of values, for δ13CDIC -27.4 to +4.5‰ and for 14CDIC +0.6 to +118 pMC. Apart from atmospheric, organic and rock leaching, input of gas at depth with similar isotopic composition as the pre-erupted melt of the upper mantle and lower crust beneath Iceland have been identified as sources for carbon in the deeper groundwater.