Allen, Katherine A.
Boron Proxies in Paleoceanography and Paleoclimatology
Boron proxies (d11B and B/Ca) were introduced nearly three decades ago, with subsequent strides being made in understanding their mechanistic functioning. This text reviews current knowledge about the aqueous systematics, the inorganic and biological controls on boron isotope fractionation and incorporation into marine carbonates, as well as the analytical techniques for measurement of boron proxies. Laboratory and field calibrations of the boron proxies are summarized, and similarities between modern calibrations are explored to suggest estimates for proxy sensitivities in marine calcifiers that are now extinct. Example applications illustrate the potential for reconstructing paleo-atmospheric pCO2 from boron isotopes. Also explored are the sensitivity of paleo-ocean acidity and pCO2 reconstructions to boron isotope proxy systematics that are currently less well understood, including the elemental and boron isotopic composition of seawater through time, seawater alkalinity, temperature and salinity, and their collective impact on the uncertainty of paleo-reconstructions.
The B/Ca proxy is based on the same mechanistic principles as the boron isotope proxy, but empirical calibrations suggest seawater pH is not the only controlling factor. B/Ca therefore has the potential to provide a second carbonate parameter that could be paired with d11B to fully constrain the ocean carbonate system, but the associated uncertainties are large. This text reviews and examines what is currently known about the B/Ca proxy systematics. As more scientists embark on characterizing past ocean acidity and atmospheric pCO2, Boron in Paleoceanography and Paleoclimatology provides a resource to introduce geoscientists to the opportunities and complications of boron proxies, including potential avenues to further refine them.
Keywords: Guide to Boron in Paleoceanography and Paleoclimatology; Review of Boron in Paleoceanography and Paleoclimatology; Text on Boron in Paleoceanography and Paleoclimatology; Resource for understanding Boron in Paleoceanography and Paleoclimatology; Boron proxies, seawater-pH and paleo-pCO2; Boron systematics; Reconstructing paleo-acidity, pCO2 and deep-ocean [CO32-]; Boron concentration and isotope ratio analysis; theoretical background of the boron isotope and B/Ca proxies; foraminifers, corals and inorganically precipitated calcium carbonate; seawater boron concentration and isotopic composition; carbonate chemistry, planktic foraminifera; Pleistocene sediment records; N-TIMS, P-TIMS, MC-ICP-MS and SIMS; aqueous systematics, Oceanography & Paleoceanography, Geochemistry & Mineralogy, Oceanography & Paleoceanography, Geochemistry & Mineralogy
- Author(s)
- Allen, Katherine A.
- Eggins, Stephen M.
- Haynes, Laura L.
- Holland, Katherine D.
- Hönisch, Bärbel
- Lorbacher, Katja
- Publisher
- John Wiley and Sons, Inc.
- Publication year
- 2019
- Language
- en
- Edition
- 1
- Imprint
- Wiley-Blackwell
- Series
- Analytical Methods in Earth and Environmental Science
- Page amount
- 248 pages
- Category
- Natural Sciences
- Format
- Ebook
- eISBN (ePUB)
- 9781119010623
- Printed ISBN
- 9781119010630