???ViewItemFull_lblHideGroup???
???ViewItemFull_lblSubject???:
???lbl_noEntry???
???ViewItemFull_lblAbstract???:
The extensive range of cationic and anionic
substitutions in minerals of the apatite
supergroup makes them valuable isotope
archives particularly for petrochronology,
paleoenvironmental studies, and ecological
research. As part of an ongoing reference
materials (RMs) development initiative at the
Potsdam SIMS user facility, we have undertaken
a study to characterize new materials for U-Pb
dating as well as sulfur and boron isotope
analyses of apatite. RMs play a crucial role for
measurements using in situ methods such as secondary ion mass spectrometry (SIMS) and
laser ablation inductively-coupled plasma mass
spectrometry (LA-ICP-MS).
Four candidate reference materials for U-Pb
dating from South Africa (3.2 Ga), Norway (1.1
Ga), Madagascar (0.5 Ga), and an unknown
locality (0.5 Ga) were studied by isotope dilution
thermal ionization mass spectrometry (ID-TIMS),
SIMS, LA-ICP-MS, electron probe microanalyzer
(EPMA), and scanning electron microscope-based
cathodoluminescence imaging (SEM-CL). The
results indicate that the LA-ICP-MS data align
well with three-dimensional total U/Pb isochron
ages determined by ID-TIMS. In contrast, the
SIMS data exhibit some inconsistencies that are
yet to be fully understood. We aim to make all
the materials accessible to the scientific
community once our characterization is
completed.
Based on SIMS homogeneity tests of nine
specimens obtained from mineralogical
collections and mineral dealers, we also
identified four promising materials for sulfur
isotope analysis. They represent a wide range of
isotope compositions (10 3δ34
SVCDT from ~4 to
~22) and S mass fractions (561–3003 μg/g).
Additionally, three samples were selected for
detailed investigation regarding B isotopes.
Further characterization of these materials will
include LA-ICP-MS and bulk measurements
across multiple laboratories, providing insights
into inter-laboratory bias.
Acknowledgements: This project has been
supported by the International Association of
Geoanalysts (Geoanalytical Research and
Networking Grants) and has received funding
from the European Union’s Horizon 2020
research and innovation programme under grant
agreement No 101005611 for Transnational
Access conducted at the SEM lab of the
Department of Geosciences, University of Oslo.
