Fig. 2: Geochemical variations at the Peruvian margin.
From: Coastal El Niño triggers rapid marine silicate alteration on the seafloor
a–f Pore water geochemistry, Ge/Si ratios, Al/Si ratios, and δ30Si values versus depth (centimetres below seafloor; cmbsf). Black horizontal lines denote the sediment-water interface (s-w interface). Values above the s-w interface are measured in bottom water samples. OMZ labels the Oxygen Minimum Zone. Error bars (2 SD of individual measurements) not shown for δ30Si are within symbol size. The δ30Si and Ge/Si ratio for feldspar as representative for reactive silicates are from Savage et al.38 and Kurtz et al.24, respectively. The δ30Si and Ge/Si ratio for diatoms are from Ehlert et al.11. and Sutton et al.20, respectively. Note the very high δ30Si for the shelf in 2017 indicating extensive authigenic clay formation.
