... MgO-Al2O3-SiO2 nesosilicates orthopyrozene orthosilicates oxides P-T conditions phase equilibria physical models silicates solubility spinel thermodynamic properties ...

... to the difficulty of accurately measuring the grain size of sands (e.g., Stevenson et al., 2023). Instead, we used a geochemical proxy for grain size, the Al2O3/SiO2 molar ratio, which has been widely applied in previous studies (Lupker et al., 2011, 2012b, 2013). Major elements were measured on bulk sand for all...

... quartz à T > 650°C, P < 5 kbar. Les relations de phases, analysées par projections de potentiels chimiques (μ Al2O3 –μ SiO2 –μ CaO ), concordent avec la séquence observée de zones de réaction, les assemblages de minéraux, et la variation observée en composition chimique du grenat, de...

... Raman and FTIR spectroscopy. The 23 samples were synthesized in the MgO SiO2 Al2O3 H2O system at 25 GPa, 1350 24 1600 . The results demonstrate that Al-bearing SiO2 glass formed by the amorphization 25 of stishovite under high-temperature conditions can incorporate water in the form of 26 hydroxyl...

... investigated Si-rich melt inclusions 27 hosted in fayalite fragments from lunar soil returned by the Chang e 5 mission. These 28 melt inclusions have high SiO2 (76.4 wt Al2O3 (11.1 wt and K2O (5.8 wt 29 and low FeO (2.8 wt TiO2 (0.42 wt and MgO (0.02 wt contents. The 30 texture and chemical composition...

... Hf(t) values ranging from +4.2 to +6.8, with Hf model ages slightly older than the formation age, which indicates a depleted mantle source metasomatized by subducted fluids or melts (Han et al., 2019). The geochemical data from the Biliya amphibolites revealed SiO2 values of 44.24 51.12 wt%; Al2O3...

... diagenetic minerals (pistomesite: PI, apatite: AP, and calcite: CC; FeO, MgO, CaO, MnO, CO2, & P2O5) occur in the material transfers involving clastic minerals (quartz: QZ, albite: AB, K-feldspar: KS, and illite: IL; SiO2, Al2O3, Na2O, & K2O; Equation 20; Stanley 2025; Korsch et al. 1993). As a result...

... diagrams illustrate clear evolutionary trends in the syenogranites (Fig. 6), where FeOT, Al2O3, MgO, Na2O, and MnO contents decrease with increasing SiO2. The chondrite-normalized REE and primitive mantlenormalized trace element diagrams reveal that the syenogranites are enriched in light rare earth...

... peridotites either. They clearly have lower MgO and NiO, Bénard, A., Le Losq, C., Müntener, O., Robyr, M., Nebel, O., Arculus, R.J., and but higher SiO2, CaO, and Na2O for a given Al2O3 content (Figs. 1A 1C), notably leading to much higher Ca/Al (~2 13). Neither metasomatic Ionov, D.A., 2022, Spinel...

... 0.00 0.00 X Mg 0.82 0.84 0.81 0.82 0.89 0.88     Mafic   to Ultramafic   SERPENTINE       ultramafite ultramafite Sample CO1414 CO1414 SiO2 41.65 41.47 Al2O3 3.28 2.90 TiO2 0.01 0.00 Cr2O3 0.04 0.07 NiO 0.24 0.23 FeO 6.66...

... of white micas on the basis of high-pressure experiments in the systems K2O–MgO–Al2O3–SiO2–H 2 O and K2O–FeO–Al2O3–SiO2–H 2 O . Lithos 41 , 229 – 250 . McKenzie , C.B. ( 1974 ): Petrology of the South Mountain Batholith, Western Nova Scotia . M. Sc. thesis, Dalhousie Univ. , Halifax, N.S...

... granodiorite samples have relatively high SiO2 (70.49 72.59 wt Al2O3 (15.13 15.82 wt and K2O (2.11 3.43 wt%) contents, relatively high Sr (727 771 ppm) and Ba (1582 2650 ppm), low Y (4.31 7.48 ppm) and Yb (0.30 0.63 ppm) contents, as well as high Sr/Y ratios of 99.27 170.46 (Table S4). They show sub-alkaline...

.... Mineral . 20 , 197 . Brown , P.A. ( 1978 ): Xonotlite: a new occurrence at Rose Blanche, Newfoundland. Can. Mineral . 16 , 671 – 672 . Buckner , D. A. , Roy , D. M. & Roy , R. ( 1960 ): Studies in the system CaO–Al2O3–SiO2–H 2 O, II. The system CaSiO3–H 2 O . Am. J...

... examined petrographically, and studied using X-ray diffraction, size fraction segregation, and lithogeochemical analysis (Korsch et al. 1993; Stanley 1997). Ten major oxide concentrations (SiO2, TiO2, Al2O3, Fe2O3T, MnO, MgO, CaO, Na2O, K2O, P2O5) were determined by fusion-XRF analysis. Loss on ignition...

..., structure, and properties of Fe-bearing aluminosilicate melts relationships among temperature, com- position, and oxygen fugacity in the system Na2O-Al2O3-SiO2-Fe-O. American Mineralogist, 74, 58 76. P D A.E. & H N. 1998. Experimental constraints on Himalayan anatexis. Journal of Petrology, 39, 689 710. P N...

... considered, but not found to be stable in any of the calculations. Components considered for the calculations were: MnO, Na2O, CaO, K2O, FeO, MgO, Al2O3, SiO2, TiO2, and H2O. Ferric iron was not included due to the presence of ilmenite as the only oxide, low Xhematite in ilmenite, as well as the presence...