Chlorine-36 dating of deep groundwater from northern sahara in the northern part of the basin, the depth of the aquifer ranges between 400 and 1800 m and the main flow direction is from west to east chlorine-36 analyses were performed on groundwater samples mainly collected along this flowpath. Due to its long half life chlorine-36 can be used to date groundwater up to 1 million years old making it useful for finding age it is a highly reactive nonmetal, and therefore is rarely found in nature. Water resources research, vol 27, no 12, pages 3201-3213, december 1991 o chlorine 36 dating of very old groundwater further studies in the great artesian basin, australia.
Depth profile of 36cl/cl ratio in groundwater was investigated in the tsukuba upland from the vertical distribution of 36 cl, the total bomb-produced 36 cl fallout over the upland is 23 × 10 12 atoms/m 2 , which corresponds to a scaling factor of 096. 36 cl concentration in groundwater does not reflect the input of bomb pulse 36 cl, and it belongs to the era before 1950 keywords: aquifer , chlorine-36 , environmental radioactive tracer , groundwater dating , icp-ms , lsc , saudi arabia. Chlorine-36, with its long half-life (301,000 a), is a good candidate to obtain information about residence time of ci groundwater some 36 cl measurements were performed for groundwater dating in the great oriental erg as early as 1985 ( fontes et al, 1985 , guendouz, 1985 , michelot et al, 1989a .
Torgersen t and phillips fm (1993) reply to comment on chlorine 36 dating of very old groundwater, 3, further results on the great artesian basin, australia by t torgerson et al by jn andrews and j-c fontes. In the utilisation of 36 cl in groundwater dating studies, the possible effects of the 36 cl concentration dispersion on the 36 cl/cl ratios in the groundwater should be correlated the distribution of 36 cl-based residence times is basically consistent with the estimated residence times from extrapolated velocity. Provide an improved baseline for studies utilizing 36clan important assumption is that the 36cl content of actively circulating groundwater prior to 1952 is related directly to. Who dating chris winters the global collective of industrial use and mine is the range of groundwater levels c dating secondary effects on dating violence young groundwater pdf format, p remote towns, california is one of irrigation inter-comparison exercises on 03/09/1956. Chlorine 36 has many advantages as a dating tool for very old groundwater these advantages include a suitable half-life (301 x l0 s years), simple geochemistry, conservative behavior in groundwater, and a.
A new way of thinking about groundwater age is changing the field of groundwater age dating following a rigorous definition of age, a groundwater sample is seen not as water that recharged the flow regime at a point in the past, but as a mixture of waters that have resided in the subsurface for varying lengths of time. 515429 chlorine-36 465 5154210 iodine-129 465 51543 stable, transient tracers 466 452 groundwater dating and residence-time measurements (capillary action) serves to drive ﬂow in relatively shallow (less than a few kilometers) saturated groundwater systems, gravitational potential is. By subsurface production, and dating on the basis of the decay of atmospheric 36cl is not possible in models of simple flow regimes the 36 cl method fails to predict groundwater age accurately where groundwater chlorinity exceeds 75–150 mg kg 1. Chlorine 36 and tritium from nuclear weapons fallout as tracers for long-term liquid and vapor transport movement in desert soils water resour res, 24(11): 1877-1891. -chlorine-36, 36cl, t dating of ground water 131 real-world dating calculated age represents averag e age of many water molecules in the sample each of these mol-ecules might have had a different history in the aquifer individually, they would give different.
Chlorine 36 has many advantages as a dating tool for very old groundwater these advantages include a suitable half‐life (301 × 10 5 years), simple geochemistry, conservative behavior in groundwater, and a general absence of subsurface sources at levels comparable to the atmospheric input. He says there are a handful of isotopes for dating groundwater up to about 60 years old, there is argonne-39 for dating back to about 1,000 years and carbon-14 for about 30,000 years chlorine-36, he says, can date back about as far as krypton-81, but he says, it’s more complicated to work with. This method is known as carbon dating you may recall that researchers used this method to date kennewick man to about 9,000 years old another radioisotope, chlorine-36, is commonly used to date groundwater. Helium as a semiquantitative tool for groundwater dating in the range of 104-108 years in: isotopes of noble gases as tracers in environmental studies iaea, vienna, pp 163-178.
Chlorine-36 decays to 36s and to 36ar, with a combined half-life of 308,000 years the half-life of this hydrophilic, nonreactive isotope makes it suitable for geologic dating in the range of up to 15 million years before present. John n andrews and jean‐charles fontes, comment on “chlorine 36 dating of very old groundwater: 3, further results on the great artesian basin, australia” by t torgersen et al, water resources research, 29, 6, (1871-1874), (2010. Chlorine-36, including the natural cosmogenic component and the component produced during atmospheric nuclear testing in the 1950`s and 1960`s (bomb pulse), is being used as an isotopic tracer for groundwater infiltration studies at yucca mountain, a potential nuclear waste repository. Chlorine-36 dating of old groundwa ter fred m phillips new mexico institute of mining & technology socorro, nm, usa basic principles of 36cl chlorine-36 has been widely used for dating old groundw ater the 36cl used for this purpose is produced in the atmosphere by the interaction of cosmic rays with argon atoms.
Chlorine-36 chlorine-36 is an isotope of chlorine chlorine has two stable isotopes and one radioactive isotope: the cosmogenic isotope 36cl its half-life is 301,000 ± 2,000 years 36cl decays primarily by beta-minus decay to 36ar, and the balance to 36s. Dating with chlorofluorocarbons 5 groundwater can be applied as cfcs and sf6 for dating: insights from groundwater dating 5 groundwater, sf6 for dating young water movement or to cfc dating using cfcs are frquently used groundwater can be concluded that cfcs. Request pdf on researchgate | chlorine-36 dating of deep groundwater from northern sahara | the ``continental intercalaire'' from sahara is one of the largest confined aquifers in the world. Chlorine-36 is an isotope of chlorine chlorine has two stable isotopes and one radioactive environmental isotope: the cosmogenic isotope 36cl the ratio of 36cl to stable 37cl in the environment is ~700 × 10−15.