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Measurement of in situ-produced cosmogenic nuclides in fine-grained quartz from shale

Abstract

In situ -produced 10 Be in quartz is widely used to constrain exposure ages and denudation rates, traditionally measured in sand-sized grains. Here we report a new method for isolating fine-grained quartz from shale and demonstrate its reliability for grain sizes down to single microns. Sequential dissolution tests and analyses of grain size separates show that meteoric 10 Be is eliminated and that recoil losses during cosmogenic nuclide production are balanced by implantation from other mineral grains. High-temperature combustion leads to diffusion of meteoric 10 Be into fine-grained quartz and must be used with caution.

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BibTeXRIS

Xianmei Huang, Darryl E. Granger, William E. Odom, Brody Conner, Lan Luo. 2025. Measurement of in situ-produced cosmogenic nuclides in fine-grained quartz from shale. https://doi.org/10.1016/j.nimb.2025.165913

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