| Autor: |
Luís Aires-Barros, José M. Marques, R. C. Graça, Paula M. Carreira |
| Rok vydání: |
2008 |
| Předmět: |
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| Zdroj: |
Applied Geochemistry. 23:2817-2828 |
| ISSN: |
0883-2927 |
| DOI: |
10.1016/j.apgeochem.2008.04.004 |
| Popis: |
The use of radioactive isotopes plays a very important role in dating groundwater, providing an apparent age of the systems in the framework of the aquifers conceptual modelling making available important features about the water fluxes, such as recharge, horizontal flow rates and discharge. In this paper, special emphasis has been put on isotopic constraints in the use of δ 13 C and 14 C content as a dating tool in some hot (76 °C) and cold (17 °C) CO 2 -rich mineral waters discharging in the Vilarelho da Raia–Pedras Salgadas region (N-Portugal). The radiocarbon content determined in these CO 2 -rich mineral waters ( 14 C activity from 4.3 up to 9.9 pmc) is incompatible with the systematic presence of 3 H (from 1.7 to 7.9 TU). The δ 13 C values of the studied CO 2 -rich mineral waters indicate that the total C in the recharge waters is being masked by larger quantities of CO 2 ( 14 C-free) introduced from deep-seated (upper mantle) sources. This paper demonstrates that a good knowledge of mineral water systems is essential to allow hydrologists to make sound conclusions on the use of C isotopic data in each particular situation. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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