Exploration Of Activity Measurements And Equilibrium Checks For Sediment Dating Using Thick-Window Germanium Detectors

Journal Article · Wed Jun 01 00:00:00 EDT 2011 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3586091· OSTI ID:21513359

Warner, Jacob A; Gladkis, Laura G; Timmers, Heiko ^[1]; Fitzsimmons, Kathryn E ^[2]; Reynolds, Eva M ^[3]

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1. School of Physical, Environmental and Mathematical Sciences, University of New South Wales at the Australian Defence Force Academy, Canberra ACT 2602 (Australia)
2. Department of Human Evolution, Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, D-04103 Leipzig (Germany)
3. Research School of Earth Sciences, Australian National University, Canberra ACT 0200 (Australia)

Activity measurements on sediment samples for trapped-charge geological dating using gamma-ray spectroscopy are an important verification of the field-site dose rate determination. Furthermore gamma-ray spectroscopy can check if the natural decay series are in secular equilibrium which is a crucial assumption in such dating. Typically the activities of leading members of the Thorium and Uranium decay series are measured, which requires Germanium detectors with thin windows and good energy resolution in order to effectively detect the associated low energy gamma-rays. Such equipment is not always readily available. The potential of conventional Germanium detectors with thick entrance window has been explored towards routine gamma-ray spectroscopy of sediment samples using higher energy gamma-rays. Alternative isotopes, such as Ac-228 and Pb-212 for the Thorium series, and Pa-234m, Ra-226 and Bi-214 for the Uranium series, have been measured in order to determine the mass-specific activity for the respective series and possibly provide a check of secular equilibrium. In addition to measurements of the K-40 activity, with the alternative approach, the activities of both decay series can be accurately determined. The secular equilibrium condition may be tested for the Thorium series. Measurement accuracy for Pa-234m is, however, not sufficient to permit also a reliable check of equilibrium for the Uranium series.

• OSTI ID: 21513359
• Journal Information: AIP Conference Proceedings, Vol. 1336, Issue 1; Conference: CAARI 2010: 21. International Conference on the Application of Accelerators in Research and Industry, Fort Worth, TX (United States), 8-13 Aug 2010; Other Information: DOI: 10.1063/1.3586091; (c) 2011 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

07 ISOTOPES AND RADIATION SOURCES
ACCURACY
ACTINIUM 228
AGE ESTIMATION
BISMUTH 214
DOSE RATES
ENERGY RESOLUTION
EQUILIBRIUM
GAMMA RADIATION
GAMMA SPECTROSCOPY
GE SEMICONDUCTOR DETECTORS
LEAD 212
POTASSIUM 40
PROTACTINIUM 234
RADIUM 226
SEDIMENTS
THORIUM
TRAPPING
URANIUM
VERIFICATION
WINDOWS
ACTINIDE NUCLEI
ACTINIDES
ACTINIUM ISOTOPES
ALKALINE EARTH ISOTOPES
ALPHA DECAY RADIOISOTOPES
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BETA-PLUS DECAY RADIOISOTOPES
BISMUTH ISOTOPES
CARBON 14 DECAY RADIOISOTOPES
ELECTROMAGNETIC RADIATION
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
EVEN-EVEN NUCLEI
HEAVY ION DECAY RADIOISOTOPES
HEAVY NUCLEI
HOURS LIVING RADIOISOTOPES
IONIZING RADIATIONS
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LEAD ISOTOPES
LIGHT NUCLEI
MEASURING INSTRUMENTS
METALS
MINUTES LIVING RADIOISOTOPES
NANOSECONDS LIVING RADIOISOTOPES
NUCLEI
ODD-ODD NUCLEI
OPENINGS
POTASSIUM ISOTOPES
PROTACTINIUM ISOTOPES
RADIATION DETECTORS
RADIATIONS
RADIOISOTOPES
RADIUM ISOTOPES
RESOLUTION
SEMICONDUCTOR DETECTORS
SPECTROSCOPY
YEARS LIVING RADIOISOTOPES