Sub‐Permil Interlaboratory Consistency for Solution‐Based Boron Isotope Analyses on Marine Carbonates

Boron isotopes in marine carbonates are increasingly used to reconstruct seawater pH and atmospheric pCO2 through Earth’s history. While isotope ratio measurements from individual laboratories are often of high quality, it is important that records generated in different laboratories can equally be compared. Within this Boron Isotope Intercomparison Project (BIIP), we characterised the boron isotopic composition (commonly expressed in δ11B) of two marine carbonates: Geological Survey of Japan carbonate reference materials JCp‐1 (coral Porites) and JCt‐1 (giant clam Tridacna gigas). Our study has three foci: (a) to assess the extent to which oxidative pre‐treatment, aimed at removing organic material from carbonate, can influence the resulting δ11B; (b) to determine to what degree the chosen analytical approach may affect the resultant δ11B; and (c) to provide well‐constrained consensus δ11B values for JCp‐1 and JCt‐1. The resultant robust mean and associated robust standard deviation (s*) for un‐oxidised JCp‐1 is 24.36 ± 0.45‰ (2s*), compared with 24.25 ± 0.22‰ (2s*) for the same oxidised material. For un‐oxidised JCt‐1, respective compositions are 16.39 ± 0.60‰ (2s*; un‐oxidised) and 16.24 ± 0.38‰ (2s*; oxidised). The consistency between laboratories is generally better if carbonate powders were oxidatively cleaned prior to purification and measurement.

[1]  C. You,et al.  NIST RM 8301 Boron Isotopes in Marine Carbonate (Simulated Coral and Foraminifera Solutions): Inter‐laboratory δ11B and Trace Element Ratio Value Assignment , 2020, Geostandards and Geoanalytical Research.

[2]  J. Ries,et al.  Calibration of the pH-δ11B and temperature-Mg/Li proxies in the long-lived high-latitude crustose coralline red alga Clathromorphum compactum via controlled laboratory experiments , 2019, Geochimica et Cosmochimica Acta.

[3]  S. Krause,et al.  Boron isotope systematics of cultured brachiopods: Response to acidification, vital effects and implications for palaeo-pH reconstruction , 2019, Geochimica et Cosmochimica Acta.

[4]  D. Niţă,et al.  CO2 storage and release in the deep Southern Ocean on millennial to centennial timescales , 2018, Nature.

[5]  D. Niţă,et al.  CO2 storage and release in the deep Southern Ocean on millennial to centennial timescales , 2018, Nature.

[6]  C. E. Lazareth,et al.  Surface ocean pH variations since 1689 CE and recent ocean acidification in the tropical South Pacific , 2018, Nature Communications.

[7]  A. Sadekov,et al.  Application of 1013 ohm Faraday cup current amplifiers for boron isotopic analyses by solution mode and laser ablation multicollector inductively coupled plasma mass spectrometry. , 2018, Rapid communications in mass spectrometry : RCM.

[8]  J. Ries,et al.  Boron isotope sensitivity to seawater pH change in a species of Neogoniolithon coralline red alga , 2017 .

[9]  S. Comeau,et al.  Coralline algae elevate pH at the site of calcification under ocean acidification , 2017, Global change biology.

[10]  G. Foster,et al.  An improved boron isotope pH proxy calibration for the deep-sea coral Desmophyllum dianthus through sub-sampling of fibrous aragonite , 2016 .

[11]  B. Hönisch,et al.  Single laboratory comparison of MC-ICP-MS and N-TIMS boron isotope analyses in marine carbonates , 2016 .

[12]  S. Flögel,et al.  Environmental constraints on Holocene cold‐water coral reef growth off Norway: Insights from a multiproxy approach , 2016 .

[13]  K. Fabricius,et al.  Internal pH regulation facilitates in situ long-term acclimation of massive corals to end-of-century carbon dioxide conditions , 2016, Scientific Reports.

[14]  G. Cabioch,et al.  Intra-skeletal calcite in a live-collected Porites sp.: Impact on environmental proxies and potential formation process , 2016 .

[15]  D. Lemarchand,et al.  A Rapid Method for Determining Boron Concentration (ID‐ICP‐MS) and δ11B (MC‐ICP‐MS) in Vegetation Samples after Microwave Digestion and Cation Exchange Chemical Purification , 2015 .

[16]  M. Holcomb,et al.  Rapid, high-precision measurements of boron isotopic compositions in marine carbonates. , 2014, Rapid communications in mass spectrometry : RCM.

[17]  H. Elderfield,et al.  Determination of δ11B by HR-ICP-MS from mass limited samples: Application to natural carbonates and water samples , 2014 .

[18]  J. Bouchez,et al.  A fully automated direct injection nebulizer (d-DIHEN) for MC-ICP-MS isotope analysis: application to boron isotope ratio measurements , 2014 .

[19]  Y. Tamenori,et al.  Fluctuations of sulfate, S-bearing amino acids and magnesium in a giant clam shell , 2014 .

[20]  A. Vengosh,et al.  Interlaboratory Comparison of Boron Isotope Analyses of Boric Acid, Seawater and Marine CaCO3 by MC-ICPMS and NTIMS , 2013 .

[21]  F. Chabaux,et al.  Experimental dissolution vs. transformation of micas under acidic soil conditions: Clues from boron isotopes , 2013 .

[22]  P. deMenocal,et al.  Interlaboratory study for coral Sr/Ca and other element/Ca ratio measurements , 2013 .

[23]  B. Hönisch,et al.  Boron, carbon, and oxygen isotopic composition of brachiopod shells: Intra-shell variability, controls, and potential as a paleo-pH recorder , 2013 .

[24]  Paolo Montagna,et al.  Coral resilience to ocean acidification and global warming through pH up-regulation , 2012 .

[25]  D. Garbe‐Schönberg,et al.  Conditions of Mytilus edulis extracellular body fluids and shell composition in a pH‐treatment experiment: Acid‐base status, trace elements and δ11B , 2012 .

[26]  J. Bouchez,et al.  MC‐ICP‐MS Isotope Measurements with Direct Injection Nebulisation (d‐DIHEN): Optimisation and Application to Boron in Seawater and Carbonate Samples , 2011 .

[27]  D. Schmidt,et al.  Boron isotopes and B/Ca in benthic foraminifera: proxies for the deep ocean carbonate system , 2011 .

[28]  C. You,et al.  Direct separation of boron from Na- and Ca-rich matrices by sublimation for stable isotope measurement by MC-ICP-MS. , 2010, Talanta.

[29]  G. Cabioch,et al.  Abrupt sea surface pH change at the end of the Younger Dryas in the central sub-equatorial Pacific inferred from boron isotope abundance in corals ( Porites ) , 2010 .

[30]  G. Foster,et al.  Boron and magnesium isotopic composition of seawater , 2010 .

[31]  G. Paris,et al.  Investigating boron isotopes in a middle Jurassic micritic sequence: Primary vs. diagenetic signal , 2010 .

[32]  A. Finch,et al.  δ11B, Sr, Mg and B in a modern Porites coral: the relationship between calcification site pH and skeletal chemistry , 2010 .

[33]  C. You,et al.  How well do non-traditional stable isotope results compare between different laboratories: results from the interlaboratory comparison of boron isotope measurements , 2009 .

[34]  Jaroslava Srnková,et al.  Comparison of different approaches to the statistical evaluation of proficiency tests , 2009 .

[35]  G. Foster Seawater pH, pCO2 and [CO2−3] variations in the Caribbean Sea over the last 130 kyr: A boron isotope and B/Ca study of planktic foraminifera , 2008 .

[36]  A. J. Kaufman,et al.  Experimental measurement of boron isotope fractionation in seawater , 2006 .

[37]  B. Hönisch,et al.  Surface ocean pH response to variations in pCO2 through two full glacial cycles , 2005 .

[38]  Y. Dauphin,et al.  The two-step mode of growth in the scleractinian coral skeletons from the micrometre to the overall scale. , 2005, Journal of structural biology.

[39]  R. Zeebe Stable boron isotope fractionation between dissolved B(OH)3 and B(OH)4 , 2005 .

[40]  A. Meixner,et al.  Air handling in clean laboratory environments: the reason for anomalously high boron background levels , 2005, Analytical and bioanalytical chemistry.

[41]  H. Kawahata,et al.  Concentrations of Trace Elements in Carbonate Reference Materials Coral JCp‐1 and Giant Clam JCt‐1 by Inductively Coupled Plasma‐Mass Spectrometry , 2004 .

[42]  G. Hanson,et al.  Assessing scleractinian corals as recorders for paleo-pH: Empirical calibration and vital effects , 2004 .

[43]  J. Gattuso,et al.  Effect of pCO2 and temperature on the boron isotopic composition of the zooxanthellate coral Acropora sp. , 2004, Coral Reefs.

[44]  C. France‐Lanord,et al.  pH control on oxygen isotopic composition of symbiotic corals , 2003 .

[45]  H. Elderfield,et al.  A study of cleaning procedures used for foraminiferal Mg/Ca paleothermometry , 2003 .

[46]  R. Barnes,et al.  Intercomparison of boron isotope and concentration measurements : Part II: Evaluation of results , 2003 .

[47]  B. Reynard,et al.  11B/10B analysis of geological materials by ICP–MS Plasma 54: Application to the boron fractionation between brachiopod calcite and seawater , 2002 .

[48]  H. Kawahata,et al.  Preparation of a New Geological Survey of Japan Geochemical Reference Material: Coral JCp-1 , 2002 .

[49]  D. Lemarchand,et al.  The influence of rivers on marine boron isotopes and implications for reconstructing past ocean pH , 2000, Nature.

[50]  G. Hanson,et al.  A procedure for the isotopic analysis of boron by negative thermal ionization mass spectrometry , 1994 .

[51]  A. Chivas,et al.  Coprecipitation and isotopic fractionation of boron in modern biogenic carbonates , 1991 .

[52]  A. Dickson Thermodynamics of the dissociation of boric acid in synthetic seawater from 273.15 to 318.15 K , 1990 .

[53]  Edward A. Boyle,et al.  Comparison of Atlantic and Pacific paleochemical records for the last 215,000 years : changes in deep ocean circulation and chemical inventories , 1985 .

[54]  Edward A. Boyle,et al.  Cadmium, zinc, copper, and barium in foraminifera tests , 1981 .

[55]  G. Hanson,et al.  BORON ISOTOPIC COMPOSITION AND CONCENTRATION IN MODERN MARINE CARBONATES , 1992 .

[56]  T. Oi,et al.  Boron isotope fractionation accompanying boron mineral formation from aqueous boric acid-sodium hydroxide solutions at 25°C , 1991 .

[57]  O. Lutz,et al.  11B and 10B NMR Investigations in Aqueous Solutions , 1986 .