Johanna Christina Obert
"Systematic investigation of U-series open-system behaviour in fossil reef corals by combined uranium-thorium-protactinium-radium analyses"
Fossil reef corals are an important archive in palaeoclimate research but numerous 230Th/U ages have to be rejected due to open-system behaviour. The processes behind open-system behaviour are still not completely understood.
This PhD thesis aims to improve the accuracy and precision of 230Th/U-dating of fossil reef corals and to gain a better understanding of open-system processes. In the framework of this study, a wide range of samples will be studied with a combination of 238U-234U-230Th analyses with 231Pa/235U and 226Ra/230Th analyses. This approach will yield additional information about open-system processes as well as their timing.
230Th/U-dating of fossil reef corals from Bonaire, Netherlands Antilles: Comparison of the dating suitability of theca material and bulk material
Brocas, W. M., Felis, T., Obert, J. C., Gierz, P., Lohmann, G., Scholz, D., Kölling, M., and Scheffers, S. R., 2016. Last interglacial temperature seasonality reconstructed from tropical Atlantic corals. Earth and Planetary Science Letters 449, 418-429.
Obert, J.C., Scholz, D., Felis, T., Brocas, W. M., Jochum, K. P., and Andreae, M. O., 2016. 230Th/U dating of Last Interglacial brain corals from Bonaire (southern Caribbean) using bulk and theca wall material. Geochimica et Cosmochimica Acta 178, 20-40.