Results 151 to 160 of about 1,741 (196)

A new petrogenetic grid for low‐grade metabasites

Journal of Metamorphic Geology, 1991
Abstract We have used internally‐consistent thermodynamic data to present calculated phase equilibria for the system Na2O‐CaO‐MgO‐Al2O3‐SiO2‐H2O (NCMASH), in the range 0–500° C and 0.1–10 kbar, involving the phases anorthite, glaucophane, grossular, heulandite, jadeite, laumontite, lawsonite, paragonite, prehnite, pumpellyite, stilbite, tremolite,
M. FREY, C. DE CAPITANI, J. G. LIOU
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Occurring asbestos in agricultural soils serpentinite-metabasite derivate (Calabria, southern Italy)

Rendiconti Online della Società Geologica Italiana, 2016
Since soils that developed on serpentinite-metabasite bedrocks could be rich in asbestos minerals which are known to have a negative impact on agricultural activity and on environmental quality, six agricultural soil samples close to the urban centers of Conflenti and Decollatura (Sila Piccola, Calabria) have been collected and characterized by using ...
Bloise A, Catalano M, PUNTURO, Rosalda
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The Austridic eclogites, metabasites and metaultrabasites from the Pohorje area (Eastern Alps, Yugoslavia): 2. The metabasites and metaultrabasites, and concluding considerations

Rendiconti Lincei, 1991
Petrography, mineral chemistry, metamorphic evolution and geothermo-barometric estimations concerning the Pohorje metabasites and metaultrabasites are presented and discussed. Consistently with the evolution detected in the associated eclogites, and disregarding serpentinization, these rocks record a three-stage metamorphic evolution: (i) an older, dry,
HINTERLECHNERRAVNIK A., SASSI F.P., VISONA', DARIO   +2 more
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Premetamorphic lateritisation in Proterozoic metabasites of Rogaland, SW Norway

Contributions to Mineralogy and Petrology, 1989
Heterogeneous layers of granulite facies metamorphic basites of the Proterozoic supracrustal Faurefjell Formation in Rogaland, S.W. Norway, display an extreme chemical variation. Within a single layer the bulk chemical composition gradually changes from approximately basaltic in basic granulites to alumina-iron-rich in granofelses. Component-ratios and
Maijer, C., Jansen, J. B. H., Bol, L. C. G. M.   +2 more
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Metabasites along the Lunvozh river (Middle Timan): petrography, mineralogy, petrochemistry

Vestnik of geosciences, 2023
A small dike of unknown age was found on the territory of the Kanin-Timan region within the Middle Timan along the Lunvozh river. Our studies revealed that the rocks, composing this intrusive body, corresponded to basaltic andesites according to the content of the main rock-forming elements.
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On a peculiar metabasite in hercynian phyllites (sicily)

TMPM Tschermaks Mineralogische und Petrographische Mitteilungen, 1976
On the basis of a mineralogical, petrological and chemical study of a “greenstone” complex intercalated in a phyllitic formation in the Western Peloritani Mountains, two main rock types can be distinguished: amphibole-chlorite metabasite (with traces of an old generation of glaucophane), and albite metabasite.
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Mafic Phyllosilicates in Low-Grade Metabasites. Characterization Using Deconvolution Analysis

Clay Minerals, 1994
AbstractThe <2 µm clay fractions from low-grade metabasalts of eastern North Greenland are mixtures of mafic phyllosilicates and celadonite that show complex X-ray diffraction (XRD) patterns. Interpretation of such patterns is difficult and subjective using only visual examination of peak positions and shapes.
Robinson, D, Bevins, RE
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Lawsonite-bearing eclogitic metabasites in the Cazadero area, northern California

Mineralogy and Petrology, 1997
In the Cazadero area, northern California, Lawsonite-bearing eclogitic metabasites occur in association with glaucophane schists. Lawsonite-bearing eclogitic metabasites are coarse-grained, and characteristically lack albite. Representative mineral assemblages are; (1) garnet + omphacite + Lawsonite + epidote + glaucophane + chlorite + quartz, (2 ...
H. Shibakusa, H. Maekawa
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Metabasites: Progressive Mineral Changes

1965
The chlorites of metabasites show a limited range of the \(Si(Mg,F{e^{2 + }}) \rightleftharpoons AlAl\) substitution, just like those of metapelites (§7B-6). The number of Si atoms on the basis of 18(O, OH) is in the range 2 5–3 O. Hence, the same formula (Mg, Fe)4.5Al3Si2.5O10(OH)8 may be used for both metabasite and metapelite chlorites. The Fe2+/(Mg
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Sodic pyroxenes from metabasites in the eastern mediterranean

Contributions to Mineralogy and Petrology, 1978
The compositions of sodic pyroxenes from blueschist metabasites in Northwest Turkey were investigated by electronprobe microanalysis. These are compared with sodic pyroxenes from high-grade blueschist terrains and eclogites with special reference to the island of Syros in Greece.
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