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Title: Measurement Background and the Sediment Age-Dating Reach of 32Si

Abstract

Silicon-32 has been identified as an isotope that fills the sediment geochronology gap created between Pb-210 at <150 years and C-14 at >1000 years. However, detector sensitivity and chemical isolation challenges of radiometric Si-32 for age dating have resulted in a fairly limited number of applications of this technique to real-world sediment studies. The significance of targeting the intermediate age bracket is to provide accurate geochronological reconstructions of paleoindicators that identify human and large-scale, climate-induced shifts in coastal areas. Therefore, we targeted Puget Sound, Washington, United States, to demonstrate the application of Si-32 age dating to determine the relative importance of climate cycles versus human activities in an in-land sea. The enhanced reconstructions will be achieved through the design of new detectors, chemical separation of biogenic silica from kilogram-scale sediment samples, and demonstration of the viable age-dating reach of Si-32. Implications of detector background on the duration of required measurements and the age-dating reach are considered. The design of a low-background, gas-proportional beta counter for measurement of the daughter isotope P-32 is discussed; detector background goals for these new detectors are based on the sensitivity study.


Citation Formats

Keillor, Martin E., Aalseth, Craig E., Arrigo, Leah M., Brandenberger, Jill M., Cloutier, Janet M., Eiden, Gregory C., Fast, James E., Finch, Zachary S., Gill, Gary A., Hossbach, Todd W., Overman, Cory T., Seiner, Brienne N., and Strivens, Jonathan E. Measurement Background and the Sediment Age-Dating Reach of 32Si. United States: N. p., 2016. Web. doi:10.1007/s10967-015-4592-5.
Keillor, Martin E., Aalseth, Craig E., Arrigo, Leah M., Brandenberger, Jill M., Cloutier, Janet M., Eiden, Gregory C., Fast, James E., Finch, Zachary S., Gill, Gary A., Hossbach, Todd W., Overman, Cory T., Seiner, Brienne N., & Strivens, Jonathan E. Measurement Background and the Sediment Age-Dating Reach of 32Si. United States. https://doi.org/10.1007/s10967-015-4592-5
Keillor, Martin E., Aalseth, Craig E., Arrigo, Leah M., Brandenberger, Jill M., Cloutier, Janet M., Eiden, Gregory C., Fast, James E., Finch, Zachary S., Gill, Gary A., Hossbach, Todd W., Overman, Cory T., Seiner, Brienne N., and Strivens, Jonathan E. 2016. "Measurement Background and the Sediment Age-Dating Reach of 32Si". United States. https://doi.org/10.1007/s10967-015-4592-5.
@article{osti_1608101,
title = {Measurement Background and the Sediment Age-Dating Reach of 32Si},
author = {Keillor, Martin E. and Aalseth, Craig E. and Arrigo, Leah M. and Brandenberger, Jill M. and Cloutier, Janet M. and Eiden, Gregory C. and Fast, James E. and Finch, Zachary S. and Gill, Gary A. and Hossbach, Todd W. and Overman, Cory T. and Seiner, Brienne N. and Strivens, Jonathan E.},
abstractNote = {Silicon-32 has been identified as an isotope that fills the sediment geochronology gap created between Pb-210 at <150 years and C-14 at >1000 years. However, detector sensitivity and chemical isolation challenges of radiometric Si-32 for age dating have resulted in a fairly limited number of applications of this technique to real-world sediment studies. The significance of targeting the intermediate age bracket is to provide accurate geochronological reconstructions of paleoindicators that identify human and large-scale, climate-induced shifts in coastal areas. Therefore, we targeted Puget Sound, Washington, United States, to demonstrate the application of Si-32 age dating to determine the relative importance of climate cycles versus human activities in an in-land sea. The enhanced reconstructions will be achieved through the design of new detectors, chemical separation of biogenic silica from kilogram-scale sediment samples, and demonstration of the viable age-dating reach of Si-32. Implications of detector background on the duration of required measurements and the age-dating reach are considered. The design of a low-background, gas-proportional beta counter for measurement of the daughter isotope P-32 is discussed; detector background goals for these new detectors are based on the sensitivity study.},
doi = {10.1007/s10967-015-4592-5},
url = {https://www.osti.gov/biblio/1608101}, journal = {Journal of Radioanalytical and Nuclear Chemistry},
number = 3,
volume = 307,
place = {United States},
year = {2016},
month = {3}
}

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