Variations in trapping temperatures and trace elements in peridotite-suite inclusions from African diamonds: evidence for two inclusion suites, and implications for lithosphere stratigraphy
Article Abstract:
Proton microprobe determines the effects of temperature in trace element contents of chrome-pyrope, olivine and orthopyroxene inclusions in African diamonds. Diamonds showing peridotite inclusions are categorized into lherzolite or subcalcic harzburgite. Peridotite inclusions that possess trapping temperatures of more than 1200 degrees centigrade are classified as lherzolytic while those that are formed at lower temperatures and considerably older are classified as subcalcic. The presence of substantial amounts of lherzolytic calcium garnets in 150-180 km suggests lherzolytic abundance at greater depths.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1992
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An experimental calibration of the "nickel in garnet" geothermometer with applications, by D. Canil: discussion
Article Abstract:
The use of unnatural compositions in D. Canil's experimental calibration of the 'nickel in garnet' geothermometer reduces its relevance in thermometry in natural systems. The lack of equilibrium in lower-temperature runs is an obstacle in the path of extrapolation to the higher-temperature results. The diffusion model used to clarify the discrepancies between the natural system and the experiments does not have corresponding proofs in nature. Canil's suggestion of a flawed basis of geothermometry is challenged by the agreement between geothermometric data and geophysical results.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1996
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Trace elements in sulphide inclusions from Yakutian diamonds
Article Abstract:
Trace element analyses, using proton microprobe, of more than 50 sulfide inclusions (SDI) from Yakutian diamonds reveal the spatial distribution of chalcophile elements in the deep lithosphere. The study also discloses the peridotitic or eclogitic paragenesis of the diamonds. Most of the inclusions in both parageneses were trapped as monosulfide solid solution. Fractionated sulfide melts are represented by a few. Multi-stage growth and resorption within magmas during diamond formation is suggested by the spatial variations of SDI compositions within single diamonds.
Publication Name: Contributions to Mineralogy and Petrology
Subject: Earth sciences
ISSN: 0010-7999
Year: 1996
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- Abstracts: Petrology and geochemistry of spinel peridotite xenoliths from the western Pannonian Basin (Hungary): evidence for an association between enrichment and texture in the upper mantle
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