Effects of Grain Size, Mineralogy, and Acid-Extractable Grain Coatings on the Distribution of Fallout Radionuclides in River Sediment

Location

King Building 337

Document Type

Presentation

Start Date

4-29-2016 1:30 PM

End Date

4-29-2016 2:30 PM

Abstract

The use of fallout radionuclides (FRNs) 7Be, 10Be, 137Cs, and unsupported 210Pb as riverine sediment tracers assumes uniform and irreversible retention. We evaluated these assumptions in two experiments: 1) Examining effects of grain size, lithology, mineralogy, and grain coating composition on the distribution of FRNs in river sediment samples, and 2) Monitoring FRN retention in samples exposed to fallout. Our findings show that FRN retention is neither uniform nor irreversible, and that FRN concentration is controlled primarily by time-dependent association with grain coatings. These findings likely explain variability of FRN concentration in river networks, exceeding variability due to differences in erosion.

Notes

Session I, Panel 4 - Media Studies: Representations of the Real in Biology and Geology
Moderator: Karla Hubbard, Associate Professor of Geology

Major

Geology; Trombone Performance

Advisor(s)

Steven Wojtal, Geology
Lee Allen, Trombone

Project Mentor(s)

Amanda Schmidt, Geology

April 2016

This document is currently not available here.

Share

COinS
 
Apr 29th, 1:30 PM Apr 29th, 2:30 PM

Effects of Grain Size, Mineralogy, and Acid-Extractable Grain Coatings on the Distribution of Fallout Radionuclides in River Sediment

King Building 337

The use of fallout radionuclides (FRNs) 7Be, 10Be, 137Cs, and unsupported 210Pb as riverine sediment tracers assumes uniform and irreversible retention. We evaluated these assumptions in two experiments: 1) Examining effects of grain size, lithology, mineralogy, and grain coating composition on the distribution of FRNs in river sediment samples, and 2) Monitoring FRN retention in samples exposed to fallout. Our findings show that FRN retention is neither uniform nor irreversible, and that FRN concentration is controlled primarily by time-dependent association with grain coatings. These findings likely explain variability of FRN concentration in river networks, exceeding variability due to differences in erosion.