Publication Date:
2024-01-09
Description:
We present the first continuous records from 0 to 5 Ma (in 0.333 m.y. integrated time steps) of paired boron/calcium (B/Ca) ratios and boron isotopes (d11B) in the planktonic foraminifera Globogerinoides sacculifer (without sacc) from a site in the western equatorial Pacific Ocean (Ocean Drilling Program Site 806). These measurements, the first made in conjunction with calcification temperature (magnesium/calcium ratios) and average shell mass measurements, indicate that pH is not the sole environmental variable controlling B in planktonic foraminiferal calcite. Our data are consistent with calcification temperature exerting a primary control on B concentration and isotopic composition in planktonic foraminifera. If so, calcification temperature must be taken into account if pH for past oceans and atmospheric pCO2 are to be estimated from B isotope measurements in foraminiferal calcite. Doing so will substantially increase the uncertainty of pH estimates. Although this work was designed as a temporal study, its results define new aspects of calibrating the d11B paleo-pH tracer.
Keywords:
130-806B; AGE; Age, maximum/old; Age, minimum/young; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Globigerinoides sacculifer, Boron/Calcium ratio; Globigerinoides sacculifer, Magnesium/Calcium ratio; Globigerinoides sacculifer, weight; Globigerinoides sacculifer, δ11B; Globigerinoides sacculifer, δ18O; Inductively coupled plasma - mass spectrometry (ICP-MS); Isotope ratio mass spectrometry; Joides Resolution; Leg130; Negative-thermal ionization mass spectrometry (N-TIMS); North Pacific Ocean; Ocean Drilling Program; ODP; Sample code/label; Sample code/label 2; Weighted
Type:
Dataset
Format:
text/tab-separated-values, 141 data points
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