Cosmogenic radionuclides

© Stephanie Neuhuber, IAG, Universität für Bodenkultur Wien

© Julia Schenk, AlpSenseBench

  • The cosmogenic nuclides 10Be (T1/2 = 1.39 Myr), 26Al (T1/2 = 717 kyr) and 36Cl (T1/2 = 301 kyr) are continuously formed by solar and cosmic radiation in the atmosphere. With their help, natural archives such as ice cores, sediments or water can be dated. If a higher or lower production of the above mentioned nuclides compared to today's rate is detected, this may indicate additional sources of cosmic radiation or changes in the magnetic fields of the earth or our sun in the past. In addition, 10Be, 26Al and 36Cl can be used to measure the duration of exposure to cosmic rays at the surface of a rock. This so-called surface exposure dating can provide information about processes on the Earth's surface and can be used, e.g. to study glacier movements.

  • The newly developed ILIAMS (Ion Laser InterAction Mass Spectrometry) setup at VERA improves the possibility to measure 26Al and 36Cl by laser-assisted isobar separation. By suppressing the isobars 26Mg and 36S by several orders of magnitude, blank values of 26Al/Al = 5×10–16 and 36Cl/Cl = 8×10–16 can be achieved at VERA.

  • As part of the RADIATE project, we worked with Science Animated to produce an animated video that explains how accelerator mass spectrometry (AMS) works. It shows fascinating applications and what we can learn about the Earth using AMS. Watch it on YouTube (link).

User guide for sample preparation

Nuclide Material(Metal) binder Cathode materialReference
10BeBeOBeO:Nb = 1:2 to 1:4
by mass
(min. 0.7 mg Nb)1		Cu (with Cu pin)Bachelor's thesis Ibrahimovic
26AlAl2O3Al2O3:Fe = 1:1 bis 1:2
by mass
(min. 0.7 mg Fe)2		Cu (with Cu pin)doi.org/10.1016/j.ijms.2021.116576
36ClAgCl-Cu (with Cu pin)

doi.org/10.1016/j.nimb.2019.05.061

41CaCaF2CaF2:PbF2 = 1:9
by mass
(min. 0.7 mg PbF2)3		Cu (with Cu pin)doi.org/10.1017/RDC.2021.73

 

Please label the sample containers as follows: for 10Be in black, for 26Al in blue, for 36Cl in green and for 41Ca with a red pen.

 

Materials used at VERA:

1: Sigma Aldrich Niobium powder <45 micron, 99.8%

2: Alfa Aesar Iron powder, 200 mesh (metals basis), 99+%

3: Thermo Fisher Lead(II) fluoride, Puratronic™, 99.997% (metals basis)

Contact:
Silke Merchel, Oscar Marchhart, Alexander Wieser
References:
  1. Steier, P., Martschini, M., Buchriegler, J., Feige, J., Lachner, J., Merchel, S., ... & Golser, R. (2019). Comparison of methods for the detection of 10Be with AMS and a new approach based on a silicon nitride foil stack. International Journal of Mass Spectrometry, 444, 116175. https://doi.org/10.1016/j.ijms.2019.116175
  2. Ruszkiczay-Rüdiger, Z., Neuhuber, S., Braucher, R., Lachner, J., Steier, P., Wieser, A., & Braun, M. (2021). Comparison and performance of two cosmogenic nuclide sample preparation procedures of in situ produced 10Be and 26Al. Journal of Radioanalytical and Nuclear Chemistry, 329(3), 1523-1536. https://doi.org/10.1007/s10967-021-07916-4
  3. Lachner, J., Marek, C., Martschini, M., Priller, A., Steier, P., & Golser, R. (2019). 36Cl in a new light: AMS measurements assisted by ion-laser interaction. Nuclear Instruments & Methods in Physics Research. Section B. Beam Interactions with Materials and Atoms, 456, 163-168. https://doi.org/10.1016/j.nimb.2019.05.061
  4. Lachner, J., Martschini, M., Kalb, A., Kern, M., Marchhart, O., Plasser, F., Priller, A., Steier, P., Wieser, A., & Golser, R. (2021). Highly sensitive Al-26 measurements by Ion-Laser-InterAction Mass Spectrometry. International Journal of Mass Spectrometry, 465, [116576]. https://doi.org/10.1016/j.ijms.2021.116576

  5. Neuhuber, S., Plan, L., Gier, S., Hintersberger, E., Lachner, J., Scholz, D., Lüthgens, C., Braumann, S., Bodenlenz, F., Voit, K., & Fiebig, M. (2020). Numerical age dating of cave sediments to quantify vertical movement at the Alpine-Carpathian transition in the Plio- and Pleistocene. Geologica Carpathica, 71(6). https://doi.org/10.31577/GeolCarp.71.6.5

Research partners:

  • Stephanie Neuhuber, Institute of Applied Geology (IAG), Universität für Bodenkultur Wien, Austria
  • Zsófia Ruszkicay-Rüdiger, Institute for Geological and Geochemical Research, Research Centre for Astronomy and Earth Sciences, ELKH, Budapest, Hungary
  • Bodo Bookhagen, Geological Remote Sensing, Institute of Geosciences, University Potsdam, Germany