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Zur geochemie der diagenese

1950; Elsevier BV; Volume: 1; Issue: 1 Linguagem: Inglês

10.1016/0016-7037(50)90008-1

1872-9533

I.Das Verhalten Von, Carl W. Correns,

Paleontology and Stratigraphy of Fossils

The changes, not caused by weathering, in a sediment between its sedimentation and metamorphism are characterized by the word diagenesis. The borderline between diagenesis and metamorphism is arbitrary and a matter of usage of language. It is questionable whether metasomatic changes are to be included. The discussion of solution and precipitation of SiO2 and CaCO3 in the sediment is based on the solubility curves of SiO2-Gel and CaCO3 in pure water at 17°C and in sea water at 20°C. Where CaCO3 is dissolved SiO2 can be precipitated and vice versa. Silification of wood is also caused by the precipitation of SiO2 due to the formation of CO2 in course of the decomposition of wood. The chemical character of the reaction between SiO2 and CaCO3 in aquatic solutions, for which the participation of H2CO3 is necessary, is briefly discussed.