Cosmogenic ²⁶Al/¹⁰Be surface production ratio in Greenland

Authors

Lee B. Corbett, University of Vermont
Paul R. Bierman, University of Vermont
Dylan H. Rood, Imperial College London
Marc W. Caffee, College of Science
Nathaniel A. Lifton, College of Science
Thomas E. Woodruff, College of Science

Document Type

Article

Publication Date

2-16-2017

Abstract

The assumed value for the cosmogenic 26Al/10Be surface production rate ratio in quartz is an important parameter for studies investigating the burial or subaerial erosion of long-lived surfaces and sediments. Recent models and data suggest that the production ratio is spatially variable and may be greater than originally thought. Here we present measured 26Al/10Be ratios for 24 continuously exposed bedrock and boulder surfaces spanning ~61–77°N in Greenland. Empirical measurements, such as ours, include nuclides produced predominately by neutron-induced spallation with percent-level contributions by muon interactions. The slope of a York regression line fit to our data is 7.3 ± 0.3 (1σ), suggesting that the 26Al/10Be surface production ratio exceeds the commonly used value of 6.75, at least in the Arctic. A higher 26Al/10Be production ratio has implications for multinuclide cosmogenic isotope studies because it results in greater modeled burial durations and erosion rates.

Rights Information

©2017. American Geophysical Union. All Rights Reserved.

Recommended Citation

Corbett, L. B., Bierman, P. R., Rood, D. H., Caffee, M. W., Lifton, N. A., and Woodruff, T. E. (2017), Cosmogenic 26Al/10Be surface production ratio in Greenland, Geophys. Res. Lett., 44, 1350– 1359, doi:10.1002/2016GL071276.

DOI

10.1002/2016GL071276