| Autor: |
Marsha Allen, David Boutt |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Water, Vol 15, Iss 24, p 4231 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2073-4441 |
| DOI: |
10.3390/w15244231 |
| Popis: |
Understanding the residence time, flow velocities, and storage volumes in fractured rock aquifers is essential for assessing the sustainable use of groundwater in island aquifer systems. Environmental tracers such as tritium (3H) and sulfur hexafluoride (SF6) that enter the aquifer systems through natural hydrological processes are effectively used to quantify the “apparent age” of young groundwater (3H results of ten wells throughout the island range between 0.02 and 0.60 TU. The groundwater samples to the south of the island possess more pre-modern groundwater ages (older ages) than samples in the north of the island. These tritium values reveal age ranges between 18 and 60–plus years. This finding suggests that fractures create flow paths oriented towards the southern parts of the basin that enable the transport of groundwater across significant topographic boundaries and watershed divides. Additionally, the data may support that southern wells are connected to isolated old sources of groundwater. SF6 values range between 0.91 and 7.97 (part per trillion volume) with an interpreted age range between 18 and 39 years. Both tracers support the original hypothesis that longer residence time waters are located south of the island except for three SF6 samples which are believed to be affected by “excess air”. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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