Chlorine 36 age dating
Potential complications include possible addition of stable Cl isotopes to the water by reactions with rocks, ion filtration (Phillips et al., 1986), or mixing with higher chloride waters.Such additions can substantially change the Cl/Cl ratios (Nimz, 1998).And to say anything sensible, you need at least two different dating techniques, based on the characteristics of the rock.
Prof Bowen's dating exercise -- also involving other dates, with two from Carn Meini, has been heavily criticised by other geologists.Some of the ideas discussed in this blog are published in my book called "The Bluestone Enigma" -- available by post and through good bookshops everywhere. To order, click I've been looking at the film called "Stonehenge -- Secrets of the Stones." Thanks to Pete for drawing attention to it.I'll put up another post with a You Tube link on it, in case anybody is interested.Cl, like Li and B, has two stable isotopes (Cl might be a useful tool for hydrograph separation analysis and determination of mixing between regional and shallow ground water mixing (Nimz, 1998).
A multi-isotopic approach is almost always beneficial ("the more isotopes the merrier! One recent example is the use the Cl of chlorinated solvents such as TCE and BTEX to identify the sources of the contaminants in ground water, and the degradation reactions that may remediate the pollution plumes.The addition of Cl can be evaluated by measurement of the Cl and other ionic concentrations in the water, in-situ production can be estimated after a measurement of aquifer U and Th concentrations, and precipitation input values can be estimated using present-day local values.