Mercury anomalies across the Palaeocene–Eocene Thermal Maximum

• DOI: 10.5194/cp-15-217-2019
• Publication Date: 2019-02-06T13:23:46Z
• Authors: Morgan T. Jones; Lawrence M. E. Pe...; Ella W. Stokke; Joost Frieling; Tamsin A. Mather; Lars Riber; Brian A. Schubert; Bo Schultz; Christian Tegner; Sverre Planke; Henrik H. Svensen
• Keywords: Mercury

Abstract. Large-scale magmatic events like the emplacement of North Atlantic Igneous Province (NAIP) are often coincident with periods extreme climate change such as Palaeocene–Eocene Thermal Maximum (PETM). One proxy for volcanism in geological record that is receiving increased attention use mercury (Hg) anomalies. Volcanic eruptions among dominant natural sources Hg to environment; thus, elevated Hg∕TOC values sedimentary rock may reflect an increase volcanic activity at time deposition. Here we focus on five continental shelf sections located around NAIP Palaeogene. We measured concentrations, total organic carbon (TOC) contents, and δ13C assess how deposition fluctuated across PETM isotope excursion (CIE). find a huge variation anomalies between sites. The Grane field Sea, most proximal locality analysed, shows concentrations up 90 100 ppb (Hg∕TOC = 95 700 wt %−1) early Eocene. Significant also present Danish (up 324 Svalbard 257 prior onset during recovery period, while section continuous anomaly body CIE. combination other tracers volcanism, tephra layers unradiogenic Os isotopes, these localities suggests pulses activity. In contrast, do not observe clear New Jersey (Bass River) or Arctic Ocean (Lomonosov Ridge). This large spatial variance could be due more regional possibility phreatomagmatic hydrothermal vent complexes formed sills led submarine release, which observed result limited distribution modern era. strata deposited CIE suggest magmatism linked contributed initiation PETM. However, evidence considerable form numerous post-PETM indicates complicated relationship LIP climate. Factors system feedbacks, changes style, and/or varying magma production rates key both cessation hyperthermal conditions processes diagenesis matter sourcing can have marked impact ratios need better constrained before considered irrefutable.