N2/Ar and Ar/He relationships: Fluid inclusion magmatic gases are measured using quadrupole mass spectrometers and the data is compared to measurements of volcanic gas analyses. Data reported by Giggenbach from active volcanoes give N2/Ar ratios in the general range of 100 to 1000 whereas corresponding Ar/He ratios vary from 100 to 2. Plotted on a Ar/He vs. N2/Ar diagram the data defines a fiel...

Mineral Compositions in Xenoliths from Malaita The report by Collerson et al. (1) of transition zone and lower mantle phases in mantle-derived material from alnöite pipes on Malaita, Solomon Islands, is highly significant in view of the rarity of such natural assemblages. Malaita is part of the obducted southern margin of the Ontong Java Plateau, an area of overthickened oceanic crust (2–7) tha...

A mathematical approach is presented for the calculation of the major and trace element fractionation that is caused by growth of zoned garnet in metamorphic rocks. This approach is based on textural and compositional parameters directly obtained from natural examples. It takes into account the mode and composition of all unzoned minerals, as well as the mode, crystal size distribution and zona...

The concentration of yttrium in pelitic garnets as a function of metamorphic grade has been examined in relation to the distribution of xenotime (YPO4) in samples from New England and British Columbia. Samples with xenotime present only as inclusions in garnet generally possess high-Y cores and concentrations that drop off discontinuously along zoning shoulders of variable width to low-Y outboa...

in the asemi-gawa area of intermediate high-pressure and low-temperature sanbagawa metamorphic belt in central shikoku, japan, piemontite-quartz schists are common in which cation exchange between piemontite and garnet has been studied. piemontite in contact with garnet usually contains two zones in which core is enriched in mn3+ and surrounded by a rim rich in fe3+. garnet is ca-fe-bearing spe...

Garnet-type solid-state electrolytes have attracted extensive attention due to their high ionic conductivity, approaching 1 mS cm-1, excellent environmental stability, and wide electrochemical stability window, from lithium metal to ∼6 V. However, to date, there has been little success in the development of high-performance solid-state batteries using these exceptional materials, the major chal...

Solid-state batteries are a promising option toward high energy and power densities due to the use of lithium (Li) metal as an anode. Among all solid electrolyte materials ranging from sulfides to oxides and oxynitrides, cubic garnet-type Li7La3Zr2O12 (LLZO) ceramic electrolytes are superior candidates because of their high ionic conductivity (10-3 to 10-4 S/cm) and good stability against Li me...

Estimates of temperatures, past and present, in geothermal reservoirs can be made by using now standard mineralogical techniques, including fluid inclusion geothermometry, vitrinite reflectance, calc-silicate and clay occurrence, the extent of clay interlayering, and measuring clay crystallinity. Recent studies of clays in 60 drillcores from 6 wells at Wairakei, for example, show an inverse rel...

Geochemistry and fluid inclusions studies were carried out on garnet and beryl from Quaternary alluvium deposits of Meluli-Namuhuca area, Mozambique. Garnet occurs as euhedral large crystals and is commonly brownish red, with a moderate brown hue in transmitted light. Apatite and ilmenite are the common inclusions. Geochemically, garnet is characterized by nearly homogenous chemical composition...

An undeformed metadolerite dyke cutting foliated pyroxene-granulite facies gneisses in the Jotunhelm, Norway, has almandine rods replacing the cores of plagioclase laths, although garnet is generally absent from the enclosing gneisses, and is not present in reaction zones between peridotites and gneisses. Chemical analyses of the dyke and its garnet, plagioclase, and clinopyroxene are given. Th...