Progress of hydration reactions in olivine–H2O and orthopyroxenite–H2O systems at 250 °C and vapor-saturated pressure

Mineral replacement rate of olivine by chrysotile and brucite under high alkaline conditions

“…This peak was shifted towards lower temperature, compared to the dehydroxylation of pure brucite peaking at 430 1C. This change of thermal stability was related to a significant incorporated amount of iron (Fe 2 þ ) into brucite structure as recently claimed by Okamoto et al [45]. Additionally we observed that weight loss ratio between serpentine and brucite is not constant following reaction advancement.…”

Textural and compositional complexities resulting from coupled dissolution–reprecipitation reactions in geomaterials

“…8h). Hierarchical fracturing provides an important means for continued fluid access during serpentinization and carbonation of peridotites (e.g., Iyer et al 2008;Kelemen and Matter 2008;Okamoto et al 2011;Plümper et al 2012;Power et al 2013). Compressional stresses that build up in systems undergoing large volume increases will result in spalling due to shear fracturing (Ulven et al 2014b).…”

Competitive hydration and dehydration at olivine–quartz boundary revealed by hydrothermal experiments: Implications for silica metasomatism at the crust–mantle boundary

“…In such a region, fluid pressure fluctuates as a result of competing dehydration and hydration reactions on the zone of silica metasomatism. The occurrences of talc veins have been reported in the serpentinized mantle peridotites in the Mid-Atlantic Ridge (Bach et al, 2004;Escartín et al, 2003) and in the subduction-related thrust zone (Peacock, 1987), which may represent fracturing induced by dehydration reaction (i.e., reaction 10) during the infiltration of Si-rich fluids (Escartín et al, 2003). It is clear that a build-up of high fluid pressure depends on several factors, including dehydration/hydration reactions, volume change, fluid flow, and the plastic deformation of rock (Wong et al, 1997).…”

“…1a). and chlorite, has been reported from oceanic fracture zones and detachment faults at the seafloor (Boschi et al, 2006;Escartín et al, 2003), as well as at exhumed subduction complexes (King et al, 2003;Peacock, 1987). The zoning of forsterite-serpentine-talcquartz has been modeled by diffusional mass transport processes coupled with multiple precipitation-dissolution reactions (Frantz and Mao, 1979;Korzhiniskii, 1970;Lichtner et al, 1986).…”