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Showing 1 to 16 of 16 for “"Augite"”.
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The Hornblende-Aegirine Augite Reaction Relationships of the Trunk Lake Granite, Maine
… indicate that the structure of aegirine augite controlled the secondary formation of hornblende in the Tunk Lake granite. In the marginal rocks of the granite body some grains of aegirine augite may be partially or completely enclosed by hornblende. Hornblende also replaces aegirine …
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Petrology and geochemistry of high degree mantle melts
… conditions. A comparison of the compositions of augite in the experiments with augite in the samples indicates that at least 4.5 wt.% H20 was present in the komatiite melts prior to emplacement. The presence of H20 in the magmas would allow them to be produced at lower temperatures than required …
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Geochemistry and petrogenesis of the Tsirub nephelinite-basanite intrusions, Aus, southern Namibia
… and clinopyroxene (diopside and aegerine-augite) occur in the two major intrusive bodies.
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A petrographical and mineralogical investigation of the rocks of the Bushveld Igneous Complex in the Tauteshoogte-Roossenekal area of the Eastern Transvaal
… large areas and which may contain a few blebs of augite exsolved from the original pigeonite. A few pigeonite grains were effectively trapped in other minerals, mostly augite, and consequently escaped reaction with the liquid. These inverted to hypersthene at the appropriate temperature and …
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Preparation of glass-ceramics largely using steelmaking slags and study on the effect of iron content on properties of glass-ceramics
… main crystalline phases formed were diopside and augite. Crystalline phases were well-distributed ranging between 0.2 to 0.4 µm after crystallization. A maximum bending strength of 91MPa and a maximum micro-hardness of 3466MPa were achieved. Effect of Al 2 O 3 content on glass-ceramics was …
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Study on preparation of high performance CaO-MgO-Al2O3-SiO2 system glass-ceramic with industrial by-products
… MPa and 89 MPa respectively. In addition, with augite and diopside as primary crystalline phase, they also had a Vickers micro-hardness of 6.2 GPa and 6.3 GPa. When applied single-stage heat treatment, sample H4 obtained a bending strength of 77.89MPa and Vickers micro-hardness of 6.5 GPa, very …
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Geology of the Christmas and Rosillos Mountains, Brewster County, Texas
… is exposed. The main mass is porphyritic olivine-augite-hornblende granite. A fault has depressed the northeast portion of the laccolith, and canyons have been eroded along faults around the southern end
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The evolution of oceanic gabbros : in-situ and ancient examples
… elsewhere. The Atlantis Bank gabbros have augites that are more primitive than plagioclases and olivines with which they coexist. Melt-rock interaction, where ascending melts dissolve the pre-existing gabbroic rocks and create hybrid magma may have caused this. Dissolution-experiments for …
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Geology and petrogenesis of the Tuscarora Intrusion of the Duluth Complex, Gillis Lake 7.5’ quadrangle, northeastern Minnesota
… The lower zone is composed of olivine gabbro to augite troctolite that is typically heterogeneous in mode and texture and locally displays modal layering and foliation. Most notably, it contains abundant, large (>100m) basaltic hornfels inclusions. The upper zone is composed of homogenous, …
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The petrology and geochemistry of Precaldera Magmas, Long Valley Caldera, Eastern California
… 1) widespread, predominately porphyritic olivine-augite basalt / trachybasalt / trachyandesite flow sequences (> 24 km³), (2) local orthopyroxene -phyric silicic trachyandesite flows (> I km³), and (3) sparsely -phyric orthopyroxene -hornblende -plagioclase quartz latite dome-flows and coarsely …
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Evolution of oceanic gabbros : in-situ and ancient examples
… elsewhere. The Atlantis Bank gabbros have augites that are more primitive than plagioclases and olivines with which they coexist. Melt-rock interaction, where ascending melts dissolve the pre-existing gabbroic rocks and create hybrid magma may have caused this. Dissolution-experiments for …
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Petrology of the Cenozoic phonolites and related rocks of the Houston Creek area, Bear Lodge Mountains, Wyoming
… They contain phenocrysts of sanidine, aegirine-augite, hauyne, sodalite, orthoclase, sphene, and melanite, with analcime, natrolite, calcite, and clays(?) occurring as major alteration products. Field relationships indicate that phonolite and trachyte porphyry were emplaced as sills within the …
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Soils and soil clay mineral formation in the Virginia Blue Ridge and Piedmont provinces
… material factors listed above. Hornblende and augite are the chief source materials of montmorillonite. Biotite possibly weathers to montmorillonite if the internal drainage is strongly retarded. Montmorillonite weathers to vermiculite in the surface horizons. Kaolinite forms early in the …
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Mineralogy and geochemistry of geophagic materials from Mashau Village in Limpopo Province, South Africa
… being the dominant minerals. Actinolite, augite, chlorite, epidote, forsterite, magnetite, muscovite, plagioclase, quartz, sepiolite and microcline were the minerals identified in rock samples. Geochemical analysis for major oxides content (SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, …
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Petrogenesis and evolution of alkalic basaltic magmas in a continental intraplate setting: the South Auckland Volcanic Field, New Zealand
… Fo₉₂). Clinopyroxene is abundant and ranges from augite (Wo₃₅₋₄₇ En₃₆₋₅₀ Fs₁₁₋₂₃) in group A to diopside (Wo₄₂₋₅₂ En₃₂₋₄₆ Fs₁₀₋₂₀) in group B basalts. Plagioclase (An₄₀₋₇₀) is found as a phenocryst only in group A basalts. The group A basalts are distinguished by their low total alkalis (3.0 - 4.8 …
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Elastic properties of mantle minerals by multiple methods and at high pressures and temperatures
Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2025-08-01