Popular article Cfc groundwater dating

Groundwater age dating with chlorofluorocarbons - Oster
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Groundwater age dating with chlorofluorocarbons - Oster

Date Dec 11, 2018

CFC-11 and CFC-12 make up 77 percent of total global production of CFCs (Derra. Freon 12). The concentration of CFCs in ground water is a function of the atmospheric CFC concentration at …. CFC‐12 and CFC‐113 were also measured, and while it appears that CFC contamination or degradation complicate the use of CFCs for age dating in some areas of the system, CFC‐11 is included in the analysis simply as an example of deriving groundwater dissolved gas …

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Tracing and Dating Young Ground Water - USGS
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Tracing and Dating Young Ground Water - USGS

Date Dec 12, 2018

CFC-13 is a trace atmospheric gas with a dating range in groundwater of about 1965 to modern. CFC-13 has been used primarily in very low-temperature refrigeration; thus groundwater environments. Home dating groundwater in front of your computer all day in search of a groundwater dating cfc serious relationship. Conscious eating will inform and empower south asian communities also plays a …

Dating of young groundwater using four anthropogenic trace
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Dating of young groundwater using four anthropogenic trace

Date Dec 6, 2018

CFC dating of groundwater is based on the assumption that historical CFC concentrations in the unsaturated zone, or in the air that was last in contact with the water, are known or can be calculated. The effect of unsaturated zone thickness on CFC dating of groundwater is discussed in the section on unsaturated zone thickness. Determining ground-water ages Ground-water dating with CFC-11, CFC-12 and CFC-113 is possible because (1) their amounts in the atmosphere over the past 50 years have been reconstructed, (2) their solubilities in water are known, and (3) concentrations in air and young water are high enough that they can be measured. Age is determined from CFCs

Age Dating of Shallow Groundwater with Chlorofluorocarbons
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Age Dating of Shallow Groundwater with Chlorofluorocarbons

Date Dec 8, 2018

Groundwater dating using anthropogenic and natural tracer substances is a powerful tool for understanding groundwater dynamics for improved management of groundwater resources. . The concentrations of chlorofluorocarbons (CFC-11, CFC-12, and CFC-113) and tritium were determined in groundwater in fractured crystalline bedrock at Finnsjn, Sweden. The specific goal was to investigate the accuracy of CFC dating in such an environment, taking potential degradation and mixing of

USGS -- Isotope Tracers -- Resources
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USGS -- Isotope Tracers -- Resources

Date Dec 13, 2018

Field studies of chlorofluorocarbons (CFC'S) as a groundwater dating tool in fractured rock aquifers. Variability in Atmospheric Chlorofluorocarbons (CCl3F and Implications for Groundwater Dating obtained by converting measured CFC concentrations in groundwater to equivalent atmospheric mixing ratios using knownsolubilityrelationships(6)andrechargetemperature.

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oundwater dating techniques dating old groundwater
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oundwater dating techniques dating old groundwater

Date Dec 3, 2018

However, in soil air above the groundwater table the CFC excess variation is low-pass filtered, allowing reconstruction of the site-specific CFC input anomaly in relation to the global background. Thus local CFC soil air measurements can provide a valuable local correction factor for CFC dating and extend the applicability of CFC studies in

Accuracy of CFC groundwater dating in a crystalline
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Accuracy of CFC groundwater dating in a crystalline

Date Dec 10, 2018

tmos- and hydrospheres. Oceanographers use CFC analyses in the pg 1' range as tracers for ocean mixing processes. In hydrogeology, it has been suggested that CFCs may be used similarly for age-dating of groundwater. We reviewed studies that report on CFCs in groundwater from 16 porous and fractured aquifers on three different continents.

Occurrence and fate of chlorofluorocarbon plumes in
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Occurrence and fate of chlorofluorocarbon plumes in

Date Dec 7, 2018

CFC dating methods are based on production records that date to the early 1940s, and the preservation of atmospheric CFC concentrations in ground water at the time of recharge.

Age dating of shallow groundwater with chlorofluorocarbons
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Age dating of shallow groundwater with chlorofluorocarbons

Date Dec 9, 2018

Various environmental isotopes and tracers are used to determine the age of groundwater. Carbon-14 is used to date groundwater older than 1000 years. Chlorofluorocarbons (Freon) and tritium techniques are used to date groundwater that is less than 50 years old.