Characterization and origin of two Fe-rich bentonites from Westerwald (Germany)

François Fontaine, Gerorge E. Christidis, Johan Yans, Sofie Hollanders, Andreas Hoffman, Nathalie Fagel

Résultats de recherche: Contribution à un journal/une revueArticleRevue par des pairs

Résumé

The Westerwald region is one of the major ceramic clay mining areas of Germany. The mined clays were deposited on the weathered Rhenish massif during Eocene and Oligocene and were protected from erosion by a large alkaline basalt cover. Two Fe-rich bentonite layers exposed in quarries of the Eastern part of the Westerwald were investigated with X-ray diffraction, thermogravimetric analysis, infrared spectroscopy, optical microscopy, scanning electron microscopy, chemical analyses and cation exchange capacity (CEC). In both bentonite layers, the main mineral is a high-charge Fe-rich beidellite containing exchangeable Ca and Mg. Even if they both derive from mafic volcanic rocks, the difference in accessory minerals and trace element content leads to the conclusion that they have a different precursor. The lower bentonite layer also contains talc, saponite, halloysite, goethite and anatase. It is part of the Paleozoic bedrock and results from the weathering of a Lower Carboniferous metabasalt. The upper bentonite layer has Upper Oligocene age and has been derived from the alteration of tuffite with a composition ranging from alkali basalt to trachyte. This bentonite is linked to the first eruptions of the intraplate Cenozoic volcanic activity of the Westerwald.

langue originaleAnglais
Numéro d'article105444
journalApplied Clay Science
Volume187
Les DOIs
Etat de la publicationPublié - 15 mars 2020

Empreinte digitale Examiner les sujets de recherche de « Characterization and origin of two Fe-rich bentonites from Westerwald (Germany) ». Ensemble, ils forment une empreinte digitale unique.

Contient cette citation