Carbon and nitrogen isotope disturbances and an end-Norian (Late Triassic) extinction event

Sephton, Mark A.; Amor, Ken; Franchi, Ian A.; Wignall, Paul B.; Newton, Robert and Zonneveld, John-Paul (2002). Carbon and nitrogen isotope disturbances and an end-Norian (Late Triassic) extinction event. Geology, 30(12) pp. 1119–1122.

DOI: https://doi.org/10.1130/0091-7613(2002)030%3C1119:CANIDA%3E2.0.CO;2

Abstract

Major perturbations of organic carbon and nitrogen isotope ratios from a Norian-Rhaetian (Late Triassic) boundary section in British Columbia coincide with an extinction of the dominant, deep-water invertebrate fauna of the Late Triassic (monotids and most ammonoids). The carbon isotope excursion is attributed to the development of widespread oceanic stagnation that favored organic-rich shale deposition. The coincident nitrogen isotope excursion suggests that progressively more nitrate-limited productivity forced a change to nitrogen-fixing cyanobacteria populations as ocean stagnation created nutrient-starved conditions. The biotic crisis and geochemical events of the Norian-Rhaetian boundary predate the latest Rhaetian (end-Triassic) mass extinction. Thus, the Late Triassic interval was marked by more than one extinction event.

Viewing alternatives

Look up in Google Scholar

Metrics

Public Attention

Altmetrics from Altmetric

Number of Citations

Citations from Dimensions
No digital document available to download for this item

Item Actions

Export

About

CORE (COnnecting REpositories)

Recommendations