First study on ²³⁶ U in the Northeast Pacific Ocean using a new target preparation procedure for AMS measurements

Autor(en)

R. Eigl, P. Steier, S. R. Winkler, K. Sakata, A. Sakaguchi

Abstrakt

We succeeded in obtaining the depth profile of

²³⁶ U for a sampling station in the Northeast Pacific Ocean using only one litre of seawater sample from each depth. For this purpose, a new procedure was developed that allowed for the preparation of accelerator mass spectrometry targets for trace uranium using only 100 μg of iron carrier material. The

²³⁶ U concentrations in water samples from the Northeast Pacific Ocean showed large variations from (9.26 ± 0.42) × 10

⁶ atoms/kg at 60 m depth to (0.08 ± 0.02) × 10

⁶ atoms/kg at a depth of 3000 m. The high

²³⁶ U concentrations in surface water reflect the input of

²³⁶ U by global and local fallout from nuclear weapons tests. The low

²³⁶ U concentrations in seawater from 1500 m and below are an indicator for the low vertical diffusion of surface water to deeper layers in the North Pacific Ocean. The total inventory of

²³⁶ U on the water column was (8.35 ± 0.23) × 10

¹² atoms/m

² , which is lower compared to those of other ocean regions solely affected by global fallout on comparable latitudes. This study represents the first dataset for

²³⁶ U in the Pacific Ocean and shows the possibility of downsizing sample volumes which may help in future applications of

²³⁶ U as tracer for large ocean areas.

Organisation(en)

Isotopenphysik

Externe Organisation(en)

Hiroshima University, National Research Foundation, University of Tsukuba

Journal

Journal of Environmental Radioactivity

Band

162-163

Seiten

244-250

Anzahl der Seiten

7

ISSN

0265-931X

DOI

https://doi.org/10.1016/j.jenvrad.2016.05.025

Publikationsdatum

10-2016

Peer-reviewed

Ja

ÖFOS 2012

103013 Ionenphysik, 103037 Umweltphysik

Schlagwörter

ASJC Scopus Sachgebiete

Pollution, Waste Management and Disposal, Health, Toxicology and Mutagenesis, Environmental Chemistry

Link zum Portal

https://ucris.univie.ac.at/portal/de/publications/first-study-on-236-u-in-the-northeast-pacific-ocean-using-a-new-target-preparation-procedure-for-ams-measurements(1e3a5e0c-e429-4605-bb39-8a8d585fec84).html