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Can biogeochemistry aid in the palaeoenvironmental/early diagenesis reconstruct...

Duration of the Early Toarcian carbon isotope excursion deduced from spectral a...

The marked 3-8[per mille sign] negative carbon isotope excursion associated with the Early Toarcian oceanic anoxic event (OAE; ~ 183 myr ago) in the Early Jurassic period is thought to represent one of the most important perturbations of the C-cycle in the last 200 myr. However, the origin of this excursion remains strongly debated, primarily due to uncertainties in the estimation of its duration, which ranges ...

Carbon-isotope record of the Early Jurassic (Toarcian) Oceanic Anoxic Event fro...

The Toarcian Oceanic Anoxic Event (OAE) in the Early Jurassic (~ 183 Ma ago) was characterized by widespread near-synchronous deposition of organic-rich shales in marine settings, as well as perturbations to several isotopic systems. Characteristically, two positive carbon-isotope excursions in a range of materials are separated by an abrupt negative shift. Carbon-isotope profiles from Toarcian fossil wood coll...

Toarcian nannobiohorizons from the Lusitanian Basin (Portugal) and their calibr...

The Lower Jurassic is well represented in west-central Portugal (Lusitanian Basin), where several outcrops with exceptional exposures exist. Among these, three sites have a major interest for Geological Heritage: S. Pedro de Moel, Rabaçal and Peniche. These localities display important sections for the study of the Liassic carbonate successions, whose scientific and educational value, for the domains of Palaeon...

La Sedimentation cyclique marno-calcaire dans le Toarcien du Bassin Lusitanien ...

Dans le secteur nord du Bassin lusitanien, les sédiments toarciens montrent une alternance marne-calcaire monotoneet une organisation en séquences de díverses échelles, dont les calcaires occupent le sommet. La cyclicité de ces unités marne-calcaire est l'objet de discussions, compte-tenu de l'absence d'une échelle de temps fiable et du problème de la signification génétique des couples élémentaires marne-calca...