The “boudinage” question in the High-Ardenne Slate Belt (Belgium): a combined structural and fluid-inclusion approach

Mullions in the High-Ardenne Slate Belt (Belgium): numerical model and parameter sensitivity analysis

“…Describing these structures, Lohest et al (1908) for the first time used the terms 'boudin' and 'boudinage'. Recently, a new dynamic model for the development of these structures was independently and simultaneously proposed by Urai et al (2001) and Kenis et al (2002) (Fig. 3).…”

“…Hydraulic fracturing in regional high-pressure compartments was responsible for the formation of the veins (Kenis et al, 2002). Kenis et al (2002) proposes that these veins formed in low-grade metamorphic conditions at maximum burial depth (, 10 km).…”

“…Kenis et al (2002) proposes that these veins formed in low-grade metamorphic conditions at maximum burial depth (, 10 km). Coexisting, syngenetic aqueous and gaseous fluid inclusions of the vein quartz and chlorite geothermometry show that the veins formed at a temperature of , 350-400 8C (Darimont et al, 1988;Verhaert, 2001).…”

“…The veins acted as mechanical boundaries due to their difference in competence with respect to the psammite (Urai et al, 2001;Kenis et al, 2002). This resulted in buckling of the interface between pelite and psammite and thus the formation of mullions (Fig.…”

“…Taking into account the kinematic constraints of Kenis et al (2002), the longest period available for mullion development is therefore estimated at 10 Ma (from 335 to 325 Ma). Urai et al (2001) and Kenis et al (2002) also discussed the nomenclature relating to these structures, which were initially called 'boudins' (Lohest et al, 1908). In current usage, boudins formed by the process of layer-parallel extension of competent layers enclosed in a less competent matrix.…”