Widespread elevated atmospheric SF6 mixing ratios in the Northeastern United States: Implications for groundwater dating
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Atmospheric SF<sub>6</sub> Near a Large Urban Area
Sulfur hexafluoride (SF6) has the potential to be a valuable transient racer for dating of young ground water. However, near urban areas, there are typically numerous point sources of SF6 which have a significant impact on the temporal evolution of its atmospheric mixing ratio, thereby complicating its use as an age-dating tool. Here, we present and discuss a 12-month record of atmospheric SF6 ...
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Chlorofluorocarbons (CFCs) and sulphur hexafluoride (SF(6)) are increasingly being used to date recent groundwater components. While these trace gases are generally well-mixed in the atmosphere, there is evidence that local atmospheric excesses (LAEs) exist in some areas of the world, primarily associated with urbanisation and thereby affecting the interpretation of data derived from groundwate...
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تاریخ انتشار 2008