Publisher © Czech Geological Survey, ISSN: 2336-5757 (online), 0514-8057 (print)

Microscopic study of the silicified rocks and spongolites of the Bohemian Cretaceous Basin


Pavel Čáp

Geoscience Research Reports 39, 2006 (GRR for 2005), pages 107–108

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This paper describes silicificied rocks and spongolites from the Bohemian Cretaceous. The silicification is generally in the form of silicified bioclasts (especially as sponge spicules) or in the form of small chalcedonic nodules. Larger chalcedonic nodules usually occur in the silicified limestones with small amount of quartz grains. Silica was derived from the spicules and quartz grains. The spicules are often secondarily calcified.