The lithographic limestones of Cerin (southern Jura Mountains, France). A synthetic approach and environmental interpretation

Paul BERNIER, Georges BARALE, Jean-Paul BOURSEAU, Eric BUFFETAUT, Christian GAILLARD, Jean-Claude GALL & Sylvie WENZ

en Comptes Rendus Palevol 13 (5) - Pages 383-402

Published on 31 August 2014

This article is a part of the thematic issue French Lagerstätten and exquisitely preserved fossils

The lithographic limestones of the Cerin quarry (southern French Jura Mountains), of Late Kimmeridgian age, were famous during the 19th century for their quality and consequently the quarry was intensely exploited. From 1975 to 1994, scientific excavations were carried out in these limestones in order to investigate the depositional environment, the burial of organisms and their taphonomy. A large set of data was collected about various organisms, unusual locomotion tracks, microbial mats and emersion structures. This led to a new interpretation of the environment as a laguna overlying a previously emergent and eroded coral reef. This laguna was episodically connected to the sea by temporary channels, during storms. Lime mud was supplied both from the sea and from the surrounding emergent areas. Most organisms, both marine and terrestrial, were transported, trapped, mixed and buried in the laguna. After death, the preservation of the carcasses was favoured by the presence of microbial mats providing superficial anoxic conditions and protecting them from decaying.


Lithographic limestone, Late Jurassic, Jura Mountains, Lagerstätten, Laguna, Taphonomy

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