Coccolithophore abundance in cores 562, 563 and 569 during METEOR cruise M51/3 in the eastern Mediterranean

During the most recent event, sapropel S1 formed between 10.8 and 6.1 ka, when freshwater-driven stratification caused seafloor anoxia below ~ 1800 metres depth, as a result of both failure of deep water formation and enhanced productivity.

Here we analyse coccolith assemblages from the open eastern Mediterranean that form a West-East transect across the basin and provide insights on past environmental changes. We focus on holococcoliths, which are specifically produced by coccolithophores as part of their life cycle during the haploid phase. Since holococcolith calcification is characterised by nano-crystals highly susceptible to dissolution we are testing their potential preservation under different bottom environmental conditions, including the effect of post-depositional oxidation.