Holistic approach of pre-existing flaws on the decay of two limestones

Autor: W. De Boever, Gilles Fronteau, Matthieu Boone, Marijn Boone, Jeroen Dils, Jan Dewanckele, T. de Kock, Patric Jacobs, Loes Brabant, L. Van Hoorebeke, Veerle Cnudde
Přispěvatelé: Universiteit Gent = Ghent University [Belgium] (UGENT), Groupe d'Étude sur les Géomatériaux et Environnements Naturels, Anthropiques et Archéologiques - EA 3795 (GEGENAA), Université de Reims Champagne-Ardenne (URCA)-SFR Condorcet, Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Université de Reims Champagne-Ardenne (URCA)-Université de Picardie Jules Verne (UPJV)-Centre National de la Recherche Scientifique (CNRS)-Maison des Sciences Humaines de Champagne-Ardenne (MSH-URCA), Université de Reims Champagne-Ardenne (URCA)-Université de Reims Champagne-Ardenne (URCA)
Rok vydání: 2013
Předmět:
Zdroj: The science of the total environment
Science of the Total Environment
Science of the Total Environment, Elsevier, 2013, 447, pp.403-414. ⟨10.1016/j.scitotenv.2012.12.094⟩
ISSN: 0048-9697
1879-1026
Popis: This study aims to understand the influence of the microfacies and the determination of pre-existing flaws on the weathering behavior of two types of limestones. Therefore, both Lede and Noyant limestones were independently weathered by strong acid tests and freeze-thaw cycles. In order to characterize the weathering patterns inside the stones, a combination of high resolution X-ray CT, SEM-EDS and thin section microscopy was used. The advantage of high resolution X-ray CT is its non-destructive character and the obtained 3D structural information. By using this technique, a time-lapse sequence of the weathering patterns was obtained for both gypsum crust formation as well as crack formation due to freezing and thawing. This way, a clear link could be made with the initial non-weathered state. Thin section microscopy and SEM-EDS provided additional chemical information. The focus of this study lies in the processes that occur in the bioclast fragments in the stone and the influence of the surrounding cement or matrix. The results show that weathering patterns vary for both limestones although the causes of weathering were similar. In case of the Noyant stone, the weathering by crystallizing gypsum was mainly restricted to the microporous matrix of the stone, while in case of the Lede stone, several foraminifera and shell fragments were preferentially recrystallized. In general, the underlying microstructure determines the weathering pattern of the stone. (C) 2013 Elsevier B.V. All rights reserved.
Databáze: OpenAIRE