Coccolithophores abundance at IODP Hole 385-U1549A in Guaymas Basin, Gulf of California

The sedimentary samples studied came from cores of Hole 385-U1549A (27° 28.33167' N, 111° 28.7844' W) obtained during the International Ocean Discovery Program (IODP) Expedition 385 "Guaymas Basin and Tectonics" during September-November 2019 aboard the drilling platform "JOIDES Resolution". For this work, we studied samples from the first 40 m of Hole 385-U1549A. The Hole 385-U1549A coccolith assemblage is mainly represented by 18 taxa of which the members of Gephyrocapsa group with size >3 µm (Gephyrocapsa oceanica and Gephyrocapsa muellerae) is the dominant taxa of the assemblage with a relative abundance above 50 %. The members of the group of Gephyrocapsa with size <3 µm (Gephyrocapsa ericsonii and Gephyrocapsa aperta) shows values around 30 %. Emiliania huxleyi and Florisphaera profunda show values around 3 %. The relative abundances of the other taxa are significantly lower including Coccolithus pelagicus, Helicosphaera carteri, Syracosphaera spp., Calcidiscus leptoporus, Umbilicosphaera spp.