Metamorphic Processes in Rodingites of the Zermatt-Saas Ophiolites

Late-Alpine rodingitization in the Bellecombe meta-ophiolites (Aosta Valley, Italian Western Alps): evidence from mineral assemblages and serpentinization-derived H2-bearing brine

“…The micro-Raman spectra of minerals were obtained at the Department of Mineralogical and Petrological Sciences, the University of Torino, with an integrated micro/macro-Raman : dots, Dal Piaz and Grasso (1967);square, Dal Piaz et al (1980); diamond, Li et al (2004bLi et al ( , 2008; triangle, Panseri et al (2008); star, this study.…”

“…In the nearby upper Valtournenche-Breuil area, Aosta Valley, Dal Piaz et al (1980) reported relict HP minerals, such as Na-rich pyroxene, from the less rodingitized boudins from Les Perères-Gouffre de Bousserailles, Gobba di Rollin, and Goillet ( Figure 1). More recently, Li et al (2004aLi et al ( , 2004bLi et al ( , 2008 described the Zermatt-Saas rodingites and the hosting serpentinites from the Lichenbretter area, Swiss Western Alps (Figure 1). Although all rodingites contain vesuvianite, chlorite, and hydrogrossular, three different types were distinguished on the basis of additional minerals.…”

Petrology and geochemistry of UHP-metamorphosed ultramafic–mafic rocks from the main hole of the Chinese Continental Scientific Drilling Project (CCSD-MH), China: Fluid/melt-rock interaction

“…More detailed mineralogical studies are needed to understand its formation, but it may have been produced during breakdown of the orthopyroxene to form serpentine. It is well known that serpentine cannot accommodate calcium in its structure (Coleman, 1977;O'Hanley, 1996;Li et al, 2004aLi et al, , 2007, and that CaO released from orthopyroxene accumulates in the fluid and can combine with SiO 2 to form wollastonite. Sparse exsolution lamellae of monazite occur in some of the eclogites.…”

Petrological, Mineralogical and Geochemical Data From the Eohellenic Ophiolitic Nappe in the Island of Skyros, Greece

“…Li et al (2008) explains the formation of hydrogarnet with clinopyroxene and water participation in the reaction with plagioclase, whereas Cr-bearing hydrogarnets formation is related with Cr release from serpentinites (Li et al, 2004). The vesuvianite was most likely formed in very low CO2 conditions with water rich fluids, at 300-400 ο C (Li et al, 2004, Hatzipanagiotou et al, 2003, Li et al, 2008, Koutsovitis et al, 2013. Nevertheless, in a lower T stage and during the ophicalcite formation the chemistry of pore waters were enriched in CO2.…”

“…Li et al, 2004;Tsikouras et al, 2009;Koutsovitis et al, 2013 Most garnets are hydroandradites, while there are some small sized Cr-bearing hydrogarnets crystals (Cr2O3= 10.34wt.%). Li et al (2008) explains the formation of hydrogarnet with clinopyroxene and water participation in the reaction with plagioclase, whereas Cr-bearing hydrogarnets formation is related with Cr release from serpentinites (Li et al, 2004). The vesuvianite was most likely formed in very low CO2 conditions with water rich fluids, at 300-400 ο C (Li et al, 2004, Hatzipanagiotou et al, 2003, Li et al, 2008, Koutsovitis et al, 2013.…”