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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.
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Isotopic and trace metal records of benthic foraminifera from Florida Straits sediment cores KNR166-2-JPC80 and KNR166-2-GGC73
Two collocal cores were recovered at approx. 542 meters depth in the Bahamas side of the Florida Straits. Benthic foraminifera species Planulina ariminensis and Hoeglundina elegans, as well as Globobulimina spp., were picked from the greater-than 250-micron size fraction. Mass spectrometry methods were used to analyze P. ariminensis and Globobulimina spp. tests for carbon and oxygen isotopic ratios while H. elegans tests were analyzed for the cadmium/calcium, magnesium/calcium, and lithium/calcium ratios. The records extend from the Late Holocene to the Penultimate Glacial Maximum (Marine Isotope Stage [MIS] 6), with high sedimentation rates during peak interglacial periods (MIS 1 and 5e). Elemental ratios were measured by reductively and oxidatively cleaning the samples following Boyle and Rosenthal (1996), and then using a Thermo Finnigan Element2 Magnetic Sector Inductively Coupled Plasma-Mass Spectrometer (ICP-MS) at the Institute of Alpine and Arctic Research, University of Colorado, Boulder (INSTAAR) according to the methods of Marchitto (2006).Stable oxygen and carbon isotopic ratio data (δ18O and δ13C, respectively) for all samples of P. ariminensis and 51 out of 70 total samples of Globobulimina spp. were acquired using a Thermo MAT 253 with Kiel carbonate preparation device at the Georgia Institute of Technology (GT). 19 replicate samples of Globobulimina were analyzed at the University of Arizona with the same methods.The temperature reconstruction uses the Mg/Li-based calibration proposed by Marchitto et al. (2018)The oxygen content reconstruction uses the benthic foraminiferal epifaunal-infaunal δ13C gradient proxy, specifically the recently updated calibration described in Hoogakker et al. (2025).
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- Award ID(s):
- 1851900
- PAR ID:
- 10654189
- Publisher / Repository:
- PANGAEA
- Date Published:
- Subject(s) / Keyword(s):
- Benthic foraminifera Dissolved oxygen Florida Strait Last Interglacial Phosphate Temperature Event label DEPTH, sediment/rock AGE Planulina ariminensis, δ18O Planulina ariminensis, δ13C Globobulimina spp., δ18O Globobulimina spp., δ13C Oxygen Hoeglundina elegans, Cadmium/Calcium ratio Cadmium/Calcium ratio Hoeglundina elegans, Magnesium/Lithium ratio Bottom water temperature Gravity corer Piston corer Isotope Ratio mass spectrometer, Thermo Fisher Scientific, ThermoScientific, MAT 253 Calculated according to Hoogakker et al., 2025 ICP-MS, Thermo Finnigan, Element 2 Calculated according to Marchitto et al. (2018). KNR166-2 Knorr
- Format(s):
- Medium: X Size: 1644 data points Other: text/tab-separated-values
- Size(s):
- 1644 data points
- Sponsoring Org:
- National Science Foundation
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