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Z. dt. Geol. Ges. | 147/2 | S. :275-281, 7 Abb., 1 Tab. | en.Txt. | Stuttgart, Juni 1996 |
Relationships between oxygen and carbon isotopes, insoluble residues and bed thicknesses of Upper Jurassic lithographic limestones from Cerin
- (Jura Mountains/France)[Beziehungen zwischen Sauerstoff- und Kohlenstoffisotopen, unlöslichen Rückständen und Schichtstärken am oberjurassischen lithographischen Plattenkalk von Cerin, (Französischer Jura)]
Authoren : Walter Michael Bausch, Paul Bernier & Michael M. Joachimski
Abstract :
The peritidal lithographic limestones of Cerin have been investigated for their carbon and oxygen isotope ratios, bed thicknesses and noncarbonate contents. The carbon isotope ratios of pure limestones as well as of marls (> 1.48 % noncarbonate content) are positively correlated with the oxygen isotope ratios. Average 
18O values of limestones and marls compare very well, but marls are depleted in 13C by 1 permille compared to the limestones. Carbon isotopes values become lighter with increasing insoluble residue content. This correlation together with the observation that the thickest carbonate beds show the heaviest 13C values may point to diagenetic cause of the observed trends.