Naslov
Astronomical age constraints and extinction mechanisms of the Late Triassic Carnian crisis

Autori
Miller, Charlotte S. ; Peterse, Francien ; da Silva, Anne-Christine ; Baranyi, Viktória ; Reichart, Gert J. ; Kürschner, Wolfram M.

Izvornik
Scientific Reports (2045-2322) 7 (2017), 1; 2557, 7

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
Carnian crisis, carbon isotopes, astrochronology

Sažetak
The geological record contains evidence for numerous pronounced perturbations in the global carbon cycle, some of which are associated with mass extinction. In the Carnian (Late Triassic), evidence from sedimentology and fossil pollen points to a significant change in climate, resulting in biotic turnover, during a time termed the ‘Carnian Pluvial Episode’ (CPE). Evidence from the marine realm suggests a causal relationship between the CPE, a global ‘wet’ period, and the injection of light carbon into the atmosphere. Here we provide the first evidence from a terrestrial stratigraphic succession of at least five significant negative C-isotope excursions (CIE)’s through the CPE recorded in both bulk organic carbon and compound specific plant leaf waxes. Furthermore, construction of a floating astronomical timescale for 1.09 Ma of the Late Triassic, based on the recognition of 405 ka eccentricity cycles in elemental abundance and gamma ray (GR) data, allows for the estimation of a duration for the isotope excursion(s). Source mixing calculations reveal that the observed substantial shift(s) in δ13C was most likely caused by a combination of volcanic emissions, subsequent warming and the dissociation of methane clathrates.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA