Mass bias stabilization by Mg doping for Si stable isotope analysis by MC-ICP-MS

Oelze, Marcus; Schuessler, Jan A.; Blanckenburg, Friedhelm von

doi:10.1039/c6ja00218h

Cited by 31 publications

(51 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Samples and standard solutions were diluted to 2 ppm Si with 1% HNO 3 and introduced to the Neptune through an APEX‐HF (ESI) desolvating nebulizer. These samples were doped with a matching concentration of Mg for mass‐bias stabilization (Oelze et al, 2016) and to correct the isotopic ratios for internal mass bias (Cardinal et al, 2003). During the second session, we used a NuPlasma II MC‐ICP‐MS (Nu Instruments Ltd) at the Vegacenter in the Natural History Museum, Stockholm.…”

Section: Methodsmentioning

confidence: 99%

Constraints on Earth System Functioning at the Paleocene‐Eocene Thermal Maximum From the Marine Silicon Cycle

Fontorbe

Frings

Rocha³

et al. 2020

Paleoceanog and Paleoclimatol

View full text Add to dashboard Cite

The Paleocene-Eocene Thermal Maximum (PETM, ca. 56 Ma) is marked by a negative carbon isotope excursion (CIE) and increased global temperatures. The CIE is thought to result from the release of 13 C-depleted carbon, although the source(s) of carbon and triggers for its release, its rate of release, and the mechanisms by which the Earth system recovered are all debated. Many of the proposed mechanisms for the onset and recovery phases of the PETM make testable predictions about the marine silica cycle, making silicon isotope records a promising tool to address open questions about the PETM. We analyzed silicon isotope ratios (δ 30 Si) in radiolarian tests and sponge spicules from the Western North Atlantic (ODP Site 1051) across the PETM. Radiolarian δ 30 Si decreases by 0.6‰ from a background of 1‰ coeval with the CIE, while sponge δ 30 Si remains consistent at 0.2‰. Using a box model to test the Si cycle response to various scenarios, we find the data are best explained by a weak silicate weathering feedback, implying the recovery was mostly driven by nondiatom organic carbon burial, the other major long-term carbon sink. We find no resolvable evidence for a volcanic trigger for carbon release, or for a change in regional oceanography. Better understanding of radiolarian Si isotope fractionation and more Si isotope records spanning the PETM are needed to confirm the global validity of these conclusions, but they highlight how the coupling between the silica and carbon cycles can be exploited to yield insight into the functioning of the Earth system.

show abstract

Section: Methodsmentioning

confidence: 99%

Constraints on Earth System Functioning at the Paleocene‐Eocene Thermal Maximum From the Marine Silicon Cycle

Fontorbe

Frings

Rocha³

et al. 2020

Paleoceanog and Paleoclimatol

View full text Add to dashboard Cite

show abstract

“…δ 30 Si was determined in wet plasma mode on a Neptune Plus Multi Collector Inductively Coupled Plasma Mass Spectrometer (MC-ICPMS) (Thermo Fisher Scientific, Germany) at the ICBM, University of Oldenburg. The measurements were carried out with the standard-sample bracketing method with external normalization by magnesium doping used for correction of the mass bias (Cardinal et al, 2003;Oelze et al, 2016). Isobaric interferences of e.g., nitrogen ( 14 N 2 ) and nitric oxide ( 14 N 16 O) were avoided by medium resolution mode focusing on the left side of the peak shoulder.…”

Section: Silicon Isotope Analysesmentioning

confidence: 99%

The Influence of Water Mass Mixing and Particle Dissolution on the Silicon Cycle in the Central Arctic Ocean

2020

View full text Add to dashboard Cite

The use of the silicon isotope composition of dissolved silicon (δ 30 Si-DSi) to understand the marine silicon cycle has been increasing in recent years. Here we present δ 30 Si-DSi and δ 30 Si of biogenic silica (δ 30 Si-bSiO 2) in the intermediate to deep waters of the Central Arctic Ocean (AO) aiming at investigating in more detail the relative influence of water mass mixing and particle flux on the Si cycle in the AO. Comparing the δ 30 Si-DSi with the water mass composition derived from Optimum Multiparameter (OMP) analysis, we were able to test the influence of the water masses in the δ 30 Si-DSi distribution. We were able to show the dominant Atlantic Water (AW) influence at the stations close to the Fram Strait (station 32 and 40, δ 30 Si-DSi = 1.51 ± 0.11 , 2SEM, n = 3) and the only small δ 30 Si-DSi modification when compared to the endmember value from a previous study (δ 30 Si-DSi = 1.55). The Dense Arctic Atlantic Water, dominating from 200 to 500 m water depth (except for stations 32 and 40, where it was present only at 500 m), was marked by heavier δ 30 Si-DSi of 1.62 ± 0.06 (2SEM, n = 21). This is probably due to the influence of entraining equally dense water from the shelves. Due to productivity and Si utilization on the shelves, both water and bSiO 2 , that were transported laterally into the Central AO, were characterized by higher δ 30 Si, with δ 30 Si-bSiO 2 of 1.64 ± 0.13 (2SEM, n = 7). Particle dissolution at greater depths did not play a major role in the δ 30 Si-DSi of deep waters due to the low bSiO 2 concentrations at these greater depths. Outflowing water masses from the AO present different δ 30 Si-DSi, with lower values around 1.46 originating from the Central AO influencing predominantly DSOW and ISOW, and higher values around 2 originating from the Canadian AO influencing predominantly LSW. Those signatures correspond with the δ 30 Si-DSi found in the North Atlantic. Consequently, the AO potentially presents several isotopically different endmembers that contribute to the deep water formed in the North Atlantic.

show abstract

“…The final Si solutions as well as the standards (NBS28, diatomite) were diluted to 0.6 ppm Si in an 0.1 M HCl matrix and doped with 0.6 ppm Mg for mass-spectrometry. d 30 Si diatom was assessed on a Neptune MC-ICP-MS (multi collector inductively coupled plasma mass spectrometer) using matrix-matched sample-standard bracketing at the German Research Centre for Geosciences Potsdam (GFZ) following standard protocols (Oelze et al 2016).…”

Section: Diatom Preparation and D 30 Si Diatom Measurementsmentioning

confidence: 99%

“…Typical internal precisions of all samples were B 0.05%. In this lab a long-term precision of 0.14% (expressed as 2SD) was determined, which we use here as our analytical uncertainty estimate, determined through 133 measurements of reference material BHVO-2 (Oelze et al 2016). Signal intensities on each of the isotopes resulting from instrumental background and acid blanks were always \ 1% of sample intensities.…”

Section: Diatom Preparation and D 30 Si Diatom Measurementsmentioning

confidence: 99%

Si cycling in transition zones: a study of Si isotopes and biogenic silica accumulation in the Chesapeake Bay through the Holocene

et al. 2019

View full text Add to dashboard Cite

Si fluxes from the continents to the ocean are a key element of the global Si cycle. Due to the ability of coastal ecosystems to process and retain Si, the 'coastal filter' has the potential to alter Si fluxes at a global scale. Coastal zones are diverse systems, sensitive to local environmental changes, where Si cycling is currently poorly understood. Here, we present the first palaeoenvironmental study of estuarine biogenic silica (BSi) fluxes and silicon isotope ratios in diatoms (d 30 Si diatom) using hand-picked diatom frustules in two sediment cores (CB dist and CB prox) from the Chesapeake Bay covering the last 12000 and 8000 years, respectively. Constrained by the well-understood Holocene evolution of the Chesapeake Bay, we interpret variations in Si cycling in the context of local climate, vegetation and land use changes. d 30 Si diatom varies between ? 0.8 and ? 1.7% in both sediment cores. A Si mass balance for the Chesapeake Bay suggests much higher rates of Si retention (* 90%) within the system than seen in other coastal systems. BSi fluxes for both sediment cores co-vary with periods of sea level rise (between 9500 and 7500 a BP) and enhanced erosion due to deforestation (between 250 and 50 a BP). However, differences in d 30 Si diatom and BSi flux between the sites emphasize the importance of the seawater/ freshwater mixing ratios and locally variable Si inputs from the catchment. Further, we interpret variations in d 30 Si diatom and the increase in BSi fluxes observed since European settlement (* 250 a BP) to reflect a growing human influence on the Si cycle in the Chesapeake Bay. Thereby, land use change, especially deforestation, in the catchment is likely the major mechanism.

show abstract

Mass bias stabilization by Mg doping for Si stable isotope analysis by MC-ICP-MS

Abstract: The combined SSB + Mg technique for Si isotope measurements under ‘dry’ plasma conditions provides high tolerances against matrix effects induced by matrix mismatch or contaminant elements.

Cited by 31 publications

References 24 publications

Constraints on Earth System Functioning at the Paleocene‐Eocene Thermal Maximum From the Marine Silicon Cycle

Constraints on Earth System Functioning at the Paleocene‐Eocene Thermal Maximum From the Marine Silicon Cycle

The Influence of Water Mass Mixing and Particle Dissolution on the Silicon Cycle in the Central Arctic Ocean

Si cycling in transition zones: a study of Si isotopes and biogenic silica accumulation in the Chesapeake Bay through the Holocene

Contact Info

Product

Resources

About