- 1School of Marine Sciences, Sun Yat-sen Univerisity, Zhuhai, China (ztps0388@leeds.ac.uk)
- 2School of Earth and Environment, University of Leeds, Leeds, UK
- 3Department of Geology, School of Natural Sciences, Trinity College Dublin, Ireland
- 4School of Earth Sciences and Engineering, Sun Yat-sen University, Zhuhai, China
Marine phosphatization events cause episodic carbonate fluorapatite (CFA) precipitation on seamounts, and are commonly linked to growth hiatuses in ferromanganese (Fe-Mn) crusts, provide critical archives for reconstructing past ocean oxygen dynamics and phosphorus cycling due to the tight relationship with oceanic oxygen minimum zones(OMZs). However, the complete record of these events and their paleoenvironmental significance remains poorly understood, in large part due to poor age constraints. Here, we apply U-Pb dating to CFA in Fe-Mn crusts from Western Pacific seamounts. These data exhibit good alignment with Sr isotope ages, revealing six potential phosphatization events. This established CFA chronology tightens the timespan of phosphatization events and refines the age framework of Fe-Mn crusts. We subsequently utilize a multiproxy approach to demonstrate that the phosphatization events occurred coeval with the expansion of oceanic OMZs. The Western Pacific Fe-Mn crusts thus document major perturbations in global oceanic phosphorus cycling, which appear to have been driven by climate-induced increases in primary productivity linked to changes in global ocean circulation. These findings offer insights into potential implications for nutrient cycling, marine ecosystems, and the evolution of OMZs.
How to cite: Peng, J., Li, D., Poulton, S., O’Sullivan, G., Chew, D., Fu, Y., and Sun, X.: Episodic intensification of marine phosphorus burial and oceanic oxygen minimum zone expansion over the last 80 million years, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-2369, https://doi.org/10.5194/egusphere-egu25-2369, 2025.