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1277383 
Journal Article 
Al-26-Be-10-Ne-21 burial dating 
Balco, G; Shuster, DL 
2009 
Yes 
Earth and Planetary Science Letters
ISSN: 0012-821X
EISSN: 1385-013X 
Elsevier 
Netherlands (NLD) 
286 
3-4 
570-575 
Cosmogenic-nuclide burial dating relies on a pair of cosmic-ray-produced nuclides that are produced in the same rock or mineral target at a fixed ratio, but have different half-lives. For example, (super 26) Al and (super 10) Be are produced in quartz at (super 26) Al: (super 10) Be=6.75:1. If a sample of quartz is exposed at the surface for a time, (super 26) Al and (super 10) Be concentrations reflect this ratio; if it is then buried below the penetration depth of cosmic rays, production stops and both nuclides decay. The half-life of (super 26) Al is half that of (super 10) Be, so the (super 26) Al/ (super 10) Be ratio decreases over time and can be used to date the burial event. Because quartz derived from surface erosion and then buried by sediment accumulation is common, the method is widely applicable for dating Plio-Pleistocene clastic sediments. All (terrestrial) applications of burial dating so far have used the (super 26) Al- (super 10) Be pair. Here we show that coupling cosmogenic (super 21) Ne, which is also produced in quartz, with (super 26) Al or (super 10) Be should improve upon both the age range and accuracy of (super 26) Al- (super 10) Be burial dating. We establish the feasibility of this approach by (super 21) Ne measurements at two sites that have already been dated using (super 26) Al- (super 10) Be burial dating. Burial ages from all three nuclide pairs agree at both sites, which shows that currently accepted values for decay constants and production ratios are internally consistent. Thus, it is possible at present to increase the useful range of cosmogenic-nuclide burial dating by incorporating (super 21) Ne. Fully realizing the potential improvements in accuracy would benefit from additional estimates of (super 21) Ne/ (super 26) Al and (super 21) Ne/ (super 10) Be production ratios that are independent of the (super 26) Al and (super 10) Be decay constants. 
cosmogenic nuclides; beryllium-10; aluminum-26; neon-21; burial dating