Results 91 to 100 of about 682 (137)

Raman spectroscopy of CaCoSi2O6–Co2Si2O6 clinopyroxenes

Physics and Chemistry of Minerals, 2014
Raman spectra were collected on a set of synthetic clinopyroxenes along the series CaCoSi2O6–Co2Si2O6. Changes in peak position and peak width show: (1) evidence of a phase transition from C2/c to P21/c, at Ca0.4Co1.6Si2O6, in agreement with previous X-ray observations; (2) peak broadening for intermediate compositions, with sharper peaks close to the ...
MANTOVANI, Luciana, TRIBAUDINO, Mario, ALIATIS, Irene, LAMBRUSCHI, Erica, LOTTICI, Pier Paolo, BERSANI, Danilo   +5 more
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Potassium in Clinopyroxene Inclusions from Diamonds

Science, 1991
Analytical transmission electron microscopy, electron microprobe analyses, and single-crystal x-ray diffraction data support the conclusion that high potassium contents, up to 1.5 weight percent K 2 O, of some diopside and omphacite inclusions from diamonds represent valid clinopyroxene compositions with K in solid ...
G E, Harlow, D R, Veblen
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Clinopyroxene dissolution in basaltic melt

Geochimica et Cosmochimica Acta, 2009
Abstract The history of magmatic systems may be inferred from reactions between mantle xenoliths and host basalt if the thermodynamics and kinetics of the reactions are quantified. To study diffusive and convective clinopyroxene dissolution in silicate melts, diffusive clinopyroxene dissolution experiments were conducted at 0.47–1.90 GPa and 1509 ...
Yang Chen, Youxue Zhang
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Pb diffusion in clinopyroxene

Chemical Geology, 1998
Abstract Chemical diffusion of Pb under anhydrous, pO2-buffered conditions has been measured in natural clinopyroxenes of two different compositions: one a near-end-member diopside and the other of more iron-rich composition (∼40% diopside component).
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Transcrystalline melt migration in clinopyroxene

Contributions to Mineralogy and Petrology, 2010
Glass inclusions in clinopyroxene phenocrysts from La Sommata (Vulcano Island, Aeolian Arc) were reheated and submitted to a sustained thermal gradient. Each remelted inclusion undergoes a transient textural and chemical reequilibration and concomitantly begins to migrate along a crystallographic direction, at a small angle with the thermal gradient ...
Sonzogni, Yann, Provost, Ariel, Schiano, Pierre   +2 more
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Garnet–clinopyroxene and clinopyroxene geothermobarometry of deep mantle and crust eclogites and peridotites

Lithos, 2008
Abstract Eclogite is one of the major types of xenoliths in kimberlite. An investigation of such xenoliths provides important constraints on the distribution of P and T within the upper mantle and its chemical composition. Garnet–clinopyroxene and clinopyroxene barometers are proposed for mantle eclogites and peridotites on the basis of CaTs ...
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Garnet-clinopyroxene geothermometer

Contributions to Mineralogy and Petrology, 1979
A garnet-clinopyroxene geothermometer based on the available experimental data on compositions of coexisting phases in the system MgO-FeO-MnO-Al2O3-Na2O-SiO2 is as follows: $$T({\text{}}K) = \frac{{8288 + 0.0276 P {\text{(bar)}} + Q1 - Q2}}{{1.987 \ln K_{\text{D}} + 2.4083}}$$
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Clinopyroxenes in Kimberlites of China

Acta Geologica Sinica - English Edition, 1992
Abstract The author studied the grain size, shape, colour, altered coat, mineral species, chemical composition, end‐ member components and infrared spectra of clinopyroxenes occurring as megacryst, macrocryst and groundmass minerals, intergrowths with pyrope and ilmenite and minerals in deep‐seated xenoliths and inclusions in diamonds in kimberlites of
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Hydrothermal clinopyroxenes of the Skaergaard intrusion

Contributions to Mineralogy and Petrology, 1986
Magmatic augites reacted with high temperature aqueous solutions to form secondary calcic pyroxenes during the subsolidus cooling of the Skaergaard intrusion. Secondary, hydrothermal clinopyroxenes replace wall rock igneous augites at the margins of veins filled with calcic amphibole. These veins are up to several millimeters wide and tens of meters in
Manning, Craig E., Bird, Dennis K.
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Elasticity of an upper mantle clinopyroxene

Physics and Chemistry of Minerals, 1998
The ambient pressure elastic properties of a natural clinopyroxene (C2/c symmetry) from Kilbourne Hole, NM have been determined. In terms of end-members, diopside (CaMgSi2O6), hedenbergite (CaFeSi2O6), jadeite (NaAlSi2O6), cosmochlor (NaCrSi2O6), and Mg-Tschermak (MgAl(AlSi)O6), its composition is Di72He9Jd3Cr3Ts12.
J. M. Brown, M. D. Collins
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