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THE ATLANTA ENSTATITE CHONDRITE BRECCIA
Meteoritics, 1983Atlanta is the fifth known brecciated enstatite chondrite. It contains a centimeter‐sized troilite‐rich clast, similar to those that occur in Blithfield. All of these clasts probably formed in the solar nebula under high pS2/pO2 conditions in a gas of non‐cosmic composition.
A. Rubin
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Igneous Graphite in Enstatite Chondrites
Mineralogical Magazine, 1997AbstractIgneous graphite, a rare constituent in terrestrial mafic and ultramafic rocks, occurs in three EH and one EL enstatite chondrite impact-melt breccias as 2–150 µm long euhedral laths, some with pyramidal terminations. In contrast, graphite in most enstatite chondrites exsolved from metallic Fe-Ni as polygonal, rounded or irregular aggregates ...
Alan E. Rubin
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Geochimica et Cosmochimica Acta, 1997
Abstract Chemical compositions of eleven enstatite chondrites (1 EH5, 4 EH3, 3 EL3, I EL5, and 2 EL6) and their metal and nonmagnetic fractions determined by instrumental neutron activation analysis are reported. The abundances of nonvolatile lithophile elements, such as Al, Sc, and Mg, increase from EH to EL, while those of siderophile and ...
P. Kong, Tadashi Mori, M. Ebihara
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Abstract Chemical compositions of eleven enstatite chondrites (1 EH5, 4 EH3, 3 EL3, I EL5, and 2 EL6) and their metal and nonmagnetic fractions determined by instrumental neutron activation analysis are reported. The abundances of nonvolatile lithophile elements, such as Al, Sc, and Mg, increase from EH to EL, while those of siderophile and ...
P. Kong, Tadashi Mori, M. Ebihara
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Earth and Planetary Science Letters, 1983
Analysis of the concentration of 10 to 15 siderophile elements was made in the magnetic regions of Abee (E4) and Hvittis (E6). All elements, except Cu, W, and Fe were concentrated in the metal phase; unlike ordinary chondrites, the metal phase Abee and Hvittis consists of homogeneous, uniform grain size kamacite.
A. Rubin
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Analysis of the concentration of 10 to 15 siderophile elements was made in the magnetic regions of Abee (E4) and Hvittis (E6). All elements, except Cu, W, and Fe were concentrated in the metal phase; unlike ordinary chondrites, the metal phase Abee and Hvittis consists of homogeneous, uniform grain size kamacite.
A. Rubin
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The compositional classification of chondrites: II The enstatite chondrite groups
Geochimica et Cosmochimica Acta, 1982We present new data from a neutron activation analysis of four enstatite chondrites including the taxonomically important St. Sauveur, and discuss the classification of enstatite chondrites. The enstatite chondrites can be divided into two compositionally distinct sets; in one set abundances of nonrefractory siderophiles and moderately volatile ...
D. Sears, G. Kallemeyn, J. Wasson
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Thermal history of the Abee enstatite chondrite
Earth and Planetary Science Letters, 1978Constraints are reported on the thermal history of the constituents of the Abee enstatite chondrite. From thermal experiments on laboratory-prepared alloys, and on actual samples of the meteorite, it is concluded that the metal phase of Abee cooled from above 700 C to room temperature in less than ten hours.
J. Herndon, M. Rudee
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Composition and origin of clasts and inclusions in the Abee enstatite chondrite breccia
Geochimica et Cosmochimica Acta, 1983Abstract We report the results of an ion probe study of rare earth elements (REEs) in six unequilibrated enstatite chondrites. Oldhamite is confirmed as the major but not the only REE carrier in these meteorites. Data are also provided for other minerals (enstatite, niningerite, and alabandite) that carry detectable amounts of REEs.
D. Sears, G. Kallemeyn, J. Wasson
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MINERALOGY AND PETROLOGY OF THE YILMIA ENSTATITE CHONDRITE
Meteoritics, 1972Yilmia, a new enstatite chondrite contains moderately well defined radiating and granular chondrules. The plagioclase to enstatite ratio is appreciably higher within than outside of the two granular chondrules in our microprobe sections. Osbornite was observed within the granular chondrules, but not in the rayed chondrules or surrounding matrixMajor ...
P. Buseck, E. Holdsworth
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Intensive parameters of enstatite chondrite metamorphism
Geochimica et Cosmochimica Acta, 1989A geothermometer based on the assemblage kamacite-quartz-enstatite-oldhamite-troilite found in enstatite chondrites is described. Data obtained with the geothermometer reveal that the EL6 meteorites experienced temperatures exceeding 1000 C. These temperatures imply a metal-sulfide melting event that may have fractionated the melt from the source ...
R. Fogel, P. Hess, M. Rutherford
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A New Type of Meteoritic Diamond in the Enstatite Chondrite Abee
Science, 1992Diamonds with δ 13 C values of –2 per mil and less than 50 parts per million (by mass) nitrogen have been isolated from the Abee enstatite chondrite by the same procedure used for concentrating Cδ, the putative interstellar diamond found ubiquitously in primitive meteorites and characterized by δ 13
S. Russell +4 more
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