Sedimentary mercury as a proxy for redox oscillations during the Cambrian SPICE event in western Newfoundland

Autor: Sara B. Pruss, David A. Fike, Amy Hagen, David S. Jones, Nicholas J. Tosca
Rok vydání: 2022
Předmět:
Zdroj: Canadian Journal of Earth Sciences. 59:504-520
ISSN: 1480-3313
0008-4077
DOI: 10.1139/cjes-2021-0108
Popis: The Steptoean Positive Isotopic Carbon Excursion, or SPICE event, was a globally recorded +2‰ to +6‰ shift in δ13C values during the later Cambrian (ca. 500 Ma). The excursion is associated with regional sea level change and trilobite extinctions documented from multiple paleocontinents, yet the mechanism(s) for these events and the excursion itself are not fully understood. Recent studies have suggested that the SPICE is accompanied by global changes in redox conditions, which may have served as an extinction driver. Here, we present new geochemical and mineralogical data from an outcrop of the SPICE located along the Port au Port Peninsula in western Newfoundland. We focus on paired sedimentary mercury and glauconite enrichments as a potential redox indicator in an effort to evaluate local redox conditions during the SPICE in Newfoundland and assess the validity of Hg as a redox proxy. These strata record small mercury enrichments (
Databáze: OpenAIRE