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Title: Assessing the Precision and Accuracy of Foraminifera Elemental Analysis at Low Ratios
Abstract The minor and trace element compositions of biogenic carbonates such as foraminifera are important tools in paleoceanography research. However, most studies have focused primarily on samples with element to calcium (El/Ca) ratios higher than the El/Ca range often found in benthic foraminifera. Here, we systematically assess the precision and accuracy of foraminifera elemental analysis across a wide range of El/Ca especially at relatively low ratios, using a method on a Thermo Scientific iCAP Qc quadrupole Inductively Coupled Plasma Mass Spectrometer (ICP‐MS). We focus on two benthic foraminifera species,Hoeglundina elegansandCibicidoides pachyderma, and prepared a suite of solution standards based on their typical El/Ca ranges to correct for signal drift and matrix effects during ICP‐MS analysis and to determine analytical precision. We observe comparable precisions with published studies at high El/Ca, and higher relative standard deviations for each element at lower El/Ca, as expected from counting statistics. The overall long‐term analytical precision (2σ) of theH. elegans‐like consistency standard solutions was 6.5%, 4.6%, 5.0%, for Li/Ca, Mg/Ca, Mg/Li, and 6.4%, 10.0%, 4.2% for B/Ca, Cd/Ca, Sr/Ca. The precision forH. elegans‐like Mg/Li is equivalent to a temperature uncertainty of 0.5–1.1°C. Measurement precisions were also assessed based on three international standards (one solution and two powder standards) and replicate measurements ofH. elegansandC. pachydermasamples. We provide file templates and program scripts that can be used to design calibration and consistency standards, prepare run sequences, and convert the raw ICP‐MS data into molar ratios.  more » « less
Award ID(s):
2114579 1811305
PAR ID:
10554239
Author(s) / Creator(s):
; ;
Publisher / Repository:
Geochemistry, Geophysics, Geosystems
Date Published:
Journal Name:
Geochemistry, Geophysics, Geosystems
Volume:
25
Issue:
10
ISSN:
1525-2027
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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