Skip directly to content

Minimize RSR Award Detail

Research Spending & Results

Award Detail

Doing Business As Name:University of Hawaii
  • Joji Uchikawa
  • (808) 956-7800
Award Date:07/09/2020
Estimated Total Award Amount: $ 344,207
Funds Obligated to Date: $ 344,207
  • FY 2020=$344,207
Start Date:07/15/2020
End Date:06/30/2023
Transaction Type:Grant
Awarding Agency Code:4900
Funding Agency Code:4900
CFDA Number:47.050
Primary Program Source:040100 NSF RESEARCH & RELATED ACTIVIT
Award Title or Description:Collaborative Research: Effects of sulfate on boron incorporation into calcite: Relevance and implications for foraminiferal boron isotope and B/Ca paleo-proxies.
Federal Award ID Number:2024631
DUNS ID:965088057
Parent DUNS ID:009438664
Program:Marine Geology and Geophysics
Program Officer:
  • Daniel McCorkle
  • (703) 292-4543

Awardee Location

Street:2440 Campus Road, Box 368
Awardee Cong. District:01

Primary Place of Performance

Organization Name:University of Hawaii
Street:1000 Pope Rd.
Cong. District:01

Abstract at Time of Award

Microscopic fossil shells can provide records of ocean chemistry in the past. The boron to calcium ratio (B/Ca) and boron isotopic composition (d11B) of such fossils are widely used to record seawater pH and carbon chemistry. These records provide valuable insights into past changes in atmospheric carbon dioxide and the global carbon cycle. Recent experiments show that the addition of sulfate ions increases the amount of B incorporated into carbonate minerals. The proposed study will explore how and why B incorporation is enhanced by sulfate. It also will examine if sulfate influences the d11B of synthetic calcite. And the study will use culture experiments to assess whether the boron chemistry of biogenic calcite is impacted by seawater sulfate. This will be a crucial test of the reliability of d11B and B/Ca fossil records, since seawater sulfate has varied substantially over the last 60 million years. The project also will provide training for graduate and undergraduate students and educational outreach activities to local communities. This study integrates inorganic calcite precipitation experiments and foraminiferal culturing to investigate the mechanistic link between B incorporation and sulfate (SO42−) and its relevance to biological systems using benthic foraminifers as the model organism. First, we will comprehensively analyze δ11B, B/Ca and other trace elements (S/Ca and Na/Ca) of synthetic calcite precipitated in solutions added with aqueous B and variable amounts of SO42−. Second, we will grow sub-mm scale calcite crystals in growth solutions added with aqueous B and/or SO42−, and compare the intra-crystal distribution/zonation of B and S using a secondary ion mass spectrometer (SIMS). Finally, we will culture a well-studied species of benthic foraminifera under various seawater SO42− concentrations. If foraminiferal δ11B and B/Ca are indeed sensitive to changes in seawater SO42−, we will provide the equations to account for the SO42− effect. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

For specific questions or comments about this information including the NSF Project Outcomes Report, contact us.