Mercury contents and isotope ratios from diverse depositional environments across the Triassic–Jurassic Boundary: Towards a more robust mercury proxy for large igneous province magmatism

Mercury is gaining prominence as a proxy for large igneous province (LIP) volcanism in the sedimentary record. Despite temporal overlap between some mass extinctions and LIPs, precise timing of magmatism relative to major ecological environmental change difficult untangle, especially marine settings. Changes contents Hg rocks through time, or ‘Hg anomalies’, can help resolve LIP activity extinctions. However, questions remain unanswered about fidelity magmatism. In particular, depositional (e.g., redox) post-depositional oxidative weathering) processes affect preservation sediments. These factors pose challenges confidently using fingerprint volcanism. Here, we use anomaly at Triassic–Jurassic boundary explore opportunities associated with two approaches that may build more robust interpretation proxy: (1) measurements sediments from diverse environments, including lithologies low organic carbon content, (2) simultaneous stable isotope ratios. We present compare records five geographically disparate Upper Triassic–Lower Jurassic sections represent nearshore, mid-shelf, deep-water, carbonate platform span emplacement Central Atlantic magmatic (CAMP) end–Triassic extinction (ETE). Total contents, compositions demonstrate multiple ways which different environments impact how anomalies are expressed ancient rocks. Although observe an increase Hg/TOC during ETE each section, pattern duration enrichment differ notably sections, not always coincident CAMP activity, illustrating filter complicates ratios alone Importantly, support volcanic origin ETE, suggesting was source interval. data isotopes distinguish loading results on global scale emphasize importance making environments.