P14: Simulation of bands of Mg/Ca composition in foramniferal calcite
Supervisor: Prof. Dr. D. Wolf-Gladrow (AWI/University Bremen)
Co-Supervisor: Prof. Dr. J. Bijma (AWI/Jacobs University)
Related Partners: Prof. Dr. G. Lohmann (AWI/University Bremen)
The Mg/Ca ratio in foraminiferal calcite is used as a paleo-temperature proxy (Nürnberg et al., 1996a,b, Geochim. Cosmochim. Acta). Recently a fine structure in the Mg/Ca distribution has been discovered: Eggins et al. (Earth and Planetary Science Letters, 225, 411– 419, 2004) discovered bands with high Mg/Ca (compare Figure). This might be good news: the banding probably contains additional information not represented by the mean Mg/Ca of whole shells. A process-based (‘mechanistic’) understanding of this fine structure is still missing.
This project will specifically target the heterogeneous distribution of Mg in the shells of the planktonic foraminifer Orbulina universa. The PhD candidate will develop a mathematical model for the calcite precipitation. The model will take into account important life processes (respiration, photosynthesis) that influence the microenvironment of foraminifera. Laboratory experiments are currently conducted to understand the mechanisms controlling the banding pattern.
Applicants should have a background in physics and/or biogeochemistry. The PhD project will be associated with the section “Marine Biogeoscience”, doing experiments on proxy incorporation into planktonic or benthic foraminiferal shells and developing small scale process models in order to obtain a process-based understanding of palaeoproxies and proxy incorporation. Within the Research School it is closely related to P6.
For further information or questions please contact:
Prof. Dr. D.A. Wolf-Gladrow ([email protected])
Prof. Dr. J. Bijma ([email protected])
Related links:
Marine Biogeosciences: www.awi.de/de/forschung/fachbereiche/biowissenschaften/biogeosciences/
Paleo Climate Dynamics: www.awi.de/en/go/paleo
International Collaborators:
Dr. Gert-Jan Reichart (University of Utrecht)
Prof. Dr. Richard Zeebe (SOEST, Hawaii)
Prof. Dr. Howard Spero (Davis, University of California, USA)
Prof. Dr. Jonathan Erez (Hebrew University, Israel)
Dr. Stephen Eggins (ANU, Australia)
Please indicate project P14, when applying for this topic.