Nodules in Toarcian (Jurassic) limestones at Saint-Antonin in the valley of the Aveyron, southwestern Quercy, France, which resemble oolites but lack the concentric structure, are described and attributed to deposition of calcite around a nucleus in one single stage. Petrographic study of the limestones also reveals that dolomitization, phosphatization, and silicification have taken place simultaneously, probably as a result of biochemical processes.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.