New constraints on the release of noble gases during in vacuo crushing and application to scapolite Br–Cl–I and 40Ar/39Ar age determinations

The noble gas systematics of late-orogenic H2O–CO2 fluids, Mt Isa, Australia

“…This indicates that the largest 'in situ' radiogenic noble gas component was hosted by mineral impurities and not fluid inclusions (Kendrick et al, 2006a(Kendrick et al, , 2007(Kendrick et al, , 2008a. The short in vacuo crushing experiments utilised in this study have been shown to release noble gases from fluid inclusions but not mineral impurities (Kendrick and Phillips, 2009). …”

“…Therefore, both laboratories employed a similar air-actuated in vacuo crushing device for the sequential release of noble gases from fluid inclusions in large gram-sized samples (Matsumoto et al, 2001). In addition, smaller aliquots were sequentially analysed by crushing in modified Nupro Ò valves at the University of Melbourne (Kendrick and Phillips, 2009).…”

Hydrothermal fluids, argon isotopes and mineralization ages of the Fankou Pb–Zn deposit in south China: Insights from sphalerite 40Ar/39Ar progressive crushing

“…These studies have further documented that argon trapped in the solid phase can be effectively extracted by heating. It is noteworthy that even by applying sufficient crushing on pure K-rich mica at 400°C and 100-200 MPa (Dunlap and Kronenberg, 2001), the level of argon lost is likely to be insignificant, similar to the limit of resolution of typical dating studies, although Kendrick and Phillips (2009), while working on scapolite found a more significant contribution of what they argued to be lattice hosted argon while crushing. Moreover, it has been well documented that chemical components such as K, Ca, Cl and 40 Ar E and their ratios in fluid inclusions (by crushing) can be remarkably different from those of the solid phase (by heating crushed powders), although in some cases they yield identical ages (Turner and Bannon, 1992;Turner and Wang, 1992;Qiu, 1996;Qiu et al, 2002;Kendrick et al, 2006a,b;Qiu and Wijbrans, 2006, 2008Qiu and Jiang, 2007;Kendrick and Phillips, 2009).…”

Retrograde metamorphism of the eclogite in North Qaidam, western China: Constraints by joint 40Ar/39Ar in vacuo crushing and stepped heating

“…Previous studies have shown that crushing has little effect on the gas trapped within the crystal lattice (Dunlap and Kronenberg, 2001;Qiu et al, 2002;Qiu andWijbrans, 2006, 2008). An exception to this may be scapolite (Kendrick and Phillips, 2009b), for which argon release by crushing was described. This may be due to the relatively open crystal structure of scapolite where volatiles may have been trapped in cavities within the crystal lattice.…”

“…In addition to that, sulphide minerals (e.g., pyrite and sphalerite) Qiu and Jiang, 2007;Jiang et al, 2012), volatile-rich metamorphic minerals from hydrothermal deposits (e.g., scapolite) (Kendrick and Phillips, 2009b), and low-potassium minerals from HP/UHP metamorphic rocks (e.g., garnet) (Qiu andWijbrans, 2006, 2008) have been analyzed with some success using this dating method. In a critique of this method, Kendrick and Phillips (2009b) argued that a significant amount of lattice-hosted noble gas from scapolite can be released during prolonged crushing, but a number of studies have indicated that crushing has very little effect on the gas component that is trapped within the crystal lattice (Dunlap and Kronenberg, 2001;Qiu et al, 2002;Qiu and Jiang, 2007;Qiu and Wijbrans, 2008;Qiu et al, 2010;Jiang et al, 2012;Bai et al, 2013). This suggests that a combination of 40 Ar/ 39 Ar dating during progressive crushing and stepwise heating of the crushed powder could provide an opportunity to distinguish the gas components trapped inside fluid inclusions and on the grain boundaries of solid inclusions from the component of the gas within the crystal lattice (Villa, 2001).…”