Multistage hydration during oceanic serpentinisation revealed by in situ oxygen isotope and trace element analyses ...

• Main Authors: Vesin, Coralie, Rubatto, Daniela, Pettke, Thomas, Deloule, Etienne
• Format: Text
• Language: unknown
• Published: Elsevier Science 2023
• Subjects: 550 Earth sciences & geology; Newfoundland
• Online Access: https://dx.doi.org/10.48350/189572; https://boris.unibe.ch/189572/

Serpentinisation of mantle peridotites below the seafloor is the most important hydration reaction in the Earth’s deep water cycle. This critical step in water–rock interaction occurs over multiple serpentinisation stages and at variable temperatures and fluid compositions. We present the first study using spatially coupled in-situ analysis of oxygen isotopes (secondary ionization mass spectrometry) and trace elements (laser ablation inductively coupled plasma mass spectrometry) to unravel the multistage hydration history of oceanic serpentinites. We study samples from the Newfoundland-Iberia extended passive margins, which represents a magma-poor ocean continent transition zone (Ocean Drilling Program cores, Leg 173 Site 1070 from Iberia, Leg 210 Site 1277 from Newfoundland). The concentrations of the fluid mobile elements chlorine and boron in serpentine are used as a proxy for the salinity of the serpentinising fluid. The correlation of Cl/B with δ18Oserpentine compositions provides new insights to ...