• Login
    View Item 
    •   Home
    • Journals and Magazines
    • Meteoritics & Planetary Science
    • Meteoritics & Planetary Science, Volume 40 (2005)
    • Meteoritics & Planetary Science, Volume 40, Number 7 (2005)
    • View Item
    •   Home
    • Journals and Magazines
    • Meteoritics & Planetary Science
    • Meteoritics & Planetary Science, Volume 40 (2005)
    • Meteoritics & Planetary Science, Volume 40, Number 7 (2005)
    • View Item
    JavaScript is disabled for your browser. Some features of this site may not work without it.

    Browse

    All of UA Campus RepositoryCommunitiesTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournalThis CollectionTitleAuthorsIssue DateSubmit DateSubjectsPublisherJournal

    My Account

    LoginRegister

    About

    AboutUA Faculty PublicationsUA DissertationsUA Master's ThesesUA Honors ThesesUA PressUA YearbooksUA CatalogsUA Libraries

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Fine-grained, spinel-rich inclusions from the reduced CV chondrite Efremovka: II. Oxygen isotopic compositions

    • CSV
    • RefMan
    • EndNote
    • BibTex
    • RefWorks
    Thumbnail
    Name:
    15149-17501-1-PB.pdf
    Size:
    1.505Mb
    Format:
    PDF
    Download
    Author
    Aléon, J.
    Krot, A. N.
    McKeegan, K. D.
    MacPherson, G. J.
    Ulyanov, A. A.
    Issue Date
    2005-01-01
    Keywords
    CV chondrites
    Fine-grained inclusions
    Iron-alkali metasomatism
    oxygen isotopes
    Calcium-aluminum-rich inclusions (CAIs)
    
    Metadata
    Show full item record
    Citation
    Aléon, J., Krot, A. N., McKeegan, K. D., MacPherson, G. J., & Ulyanov, A. A. (2005). Fine‐grained, spinel‐rich inclusions from the reduced CV chondrite Efremovka: II. Oxygen isotopic compositions. Meteoritics & Planetary Science, 40(7), 1043-1058.
    Publisher
    The Meteoritical Society
    Journal
    Meteoritics & Planetary Science
    URI
    http://hdl.handle.net/10150/656021
    DOI
    10.1111/j.1945-5100.2005.tb00172.x
    Additional Links
    https://meteoritical.org/
    Abstract
    Oxygen isotopes have been measured by ion microprobe in individual minerals (spinel, Al- Ti-diopside, melilite, and anorthite) within four relatively unaltered, fine-grained, spinel-rich Ca-Alrich inclusions (CAIs) from the reduced CV chondrite Efremovka. Spinel is uniformly 16O-rich (Delta-17O is less than or equal to -20 ppm) in all four CAIs; Al-Ti-diopside is similarly 16O-rich in all but one CAI, where it has smaller 16O excesses (-15 ppm is less than or equal to Delta-17O, which is less than or equal to -10 ppm). Anorthite and melilite vary widely in composition from 16O-rich to 16O-poor (-22 ppm is less than or equal to Delta-17O, which is less than or equal to -5 ppm). Two of the CAIs are known to have group II volatilityfractionated rare-earth-element patterns, which is typical of this variety of CAI and which suggests formation by condensation. The association of such trace element patterns with 16O-enrichment in these CAIs suggests that they formed by gas-solid condensation from an 16O-rich gas. They subsequently experienced thermal processing in an 16O-poor reservoir, resulting in partial oxygen isotope exchange. Within each inclusion, oxygen isotope variations from mineral to mineral are consistent with solid-state oxygen self-diffusion at the grain-to-grain scale, but such a model is not consistent with isotopic variations at a larger scale in two of the CAIs. The spatial association of 16O depletions with both elevated Fe contents in spinel and the presence of nepheline suggests that latestage iron-alkali metasomatism played some role in modifying the isotopic patterns in some CAIs. One of the CAIs is a compound object consisting of a coarse-grained, melilite-rich (type A) lithology joined to a fine-grained, spinel-rich one. Melilite and anorthite in the fine-grained portion are mainly 16O-rich, whereas melilite in the type A portion ranges from 16O-rich to 16O-poor, suggesting that oxygen isotope exchange predated the joining together of the two parts and that both 16O-rich and 16O-poor gaseous reservoirs existed simultaneously in the early solar nebula.
    Type
    Article
    text
    Language
    en
    ISSN
    1945-5100
    ae974a485f413a2113503eed53cd6c53
    10.1111/j.1945-5100.2005.tb00172.x
    Scopus Count
    Collections
    Meteoritics & Planetary Science, Volume 40, Number 7 (2005)

    entitlement

     
    The University of Arizona Libraries | 1510 E. University Blvd. | Tucson, AZ 85721-0055
    Tel 520-621-6442 | repository@u.library.arizona.edu
    DSpace software copyright © 2002-2017  DuraSpace
    Quick Guide | Contact Us | Send Feedback
    Open Repository is a service operated by 
    Atmire NV
     

    Export search results

    The export option will allow you to export the current search results of the entered query to a file. Different formats are available for download. To export the items, click on the button corresponding with the preferred download format.

    By default, clicking on the export buttons will result in a download of the allowed maximum amount of items.

    To select a subset of the search results, click "Selective Export" button and make a selection of the items you want to export. The amount of items that can be exported at once is similarly restricted as the full export.

    After making a selection, click one of the export format buttons. The amount of items that will be exported is indicated in the bubble next to export format.