Abstract
Abstract. Measurements of cosmic-ray-produced beryllium-10, neon-21, and helium-3 in quartz in a soil profile from a forested landscape in the Oregon Coast Range show that the cosmogenic noble gases 21Ne and 3He are depleted relative to 10Be in the shallow subsurface. The noble gases are mobile in mineral grains via thermally activated diffusion and 10Be is not, implying that noble gas depletion is the result of surface heating by wildfires and subsequent mixing of partially degassed quartz downward into the soil. Cosmogenic noble gas depletion by wildfire heating of soils is a potential means of estimating wildfire intensity and/or frequency over pre-observational timescales.
Funder
Ann and Gordon Getty Foundation
Reference22 articles.
1. Baldwin, E. M. and Howell, P. W.: The Long Tom, a former tributary of the Siuslaw River, Northwest Sci., 23, 112–124, 1949. a
2. Brook, E. J. and Kurz, M. D.: Surface-exposure chronology using in situ cosmogenic 3He in Antarctic quartz sandstone boulders, Quat. Res., 39, 1–10, 1993. a
3. Dunai, T. J.: Cosmogenic nuclides: principles, concepts and applications in the Earth surface sciences, Cambridge University Press, ISBN 1108445721, 2010. a
4. Fechtig, H. and Kalbitzer, S.: The diffusion of argon in potassium-bearing solids, in: Potassium argon dating, edited by: Schaeffer, O. and Zähringer, J., Springer, 68–107, ISBN 111457709X, 1966. a
5. Gillespie, A. R., Budinger Jr., F. E., and Abbott, E. A.: Verification of prehistoric campfires by 40Ar / 39Ar analysis of fire-baked stones, J. Archaeol. Sci., 16, 271–291, 1989. a, b