Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5782908 | Chemical Geology | 2017 | 47 Pages |
Abstract
We propose that the substitution of Al3Â + for Fe3Â +, Fe2Â + and Mg2Â + in the octahedral sheet shifts the stability field of the kaolinite-Fe-Al-Mg-smectite-Fe-Al-Mg-illite (or glauconite) triple point to much lower monosilicic acid activities, and stabilizes the I-S (or Gl-S) structure. This reaction supports the idea that the (bio)availability of Fe is the rate-limiting factor for glauconitization, which is not the case for the diagenetic growth of I-S, whereby the pore water Fe2Â + concentration may be limited by the competing formation of Fe-(oxy)hydroxides and/or Fe-sulfides.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Geochemistry and Petrology
Authors
Andre Baldermann, Martin Dietzel, Vasileios Mavromatis, Florian Mittermayr, Laurence N. Warr, Klaus Wemmer,