Over geologic time an equilibrium will be established between the subsurface in-situ production of 36 Cl and its decay similar to the secular equilibrium of U isotopes.
Please contact Carol Kendall ckendall usgs. The following reaction results in the production of 36 Cl from 35 Cl in groundwater: GarnierDetermination of the initial 14 C 00activity of the total dissolved carbon: Related Content Load related web page information.
Publication History Issue online: Next article in issue: Roughly two thirds of atmospheric 36 Cl is produced by the following spallation reaction: The 35 Cl isotope has a large dating absorption cross-section, making a relatively large target for datings with thermal neutrons. GibsonExtraction technique for the determination of oxygen in water using preevacuated glass vialsAnal.
Sitte—Springer-Verlag, New York The following reactions can result:. High-energy cosmic ray particles collide with atoms in the earth's atmosphere producing protons and neutrons. Geochronological dating methods Historical geology Geomorphology Erosion. This page was last edited on 31 Octoberat These equations can be combined to give the total concentration of cosmogenic radionuclides in a sample as a function of age.
We are sorry to record that shortly after this paper was accepted for publication, Peter J. The former age, although implying early deglaciation for this area of the British ice sheet, is not incompatible with minimum deglaciation ages from other contexts and locations in northwest England.
Further constraints on the timing of the LGM deglaciation in Britain. To a smaller extent, potassium can absorb neutrons from these same decay reactions and produce 36 Cl in the following reaction:.
Valuing discrete improvements in drinking water quality through revealed preferences Next article in issue: Milk River aquifer, Alberta, Canada". Chlorine and major-element chemistryPh.