Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    Variable involvements of mantle plumes in the genesis of mid-Neoproterozoic basaltic rocks in South China: A review

    Access Status
    Fulltext not available
    Authors
    Wang, Xuan-ce
    Li, X.
    Li, W.
    Li, Zheng-Xiang
    Date
    2009
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Wang, Xuan-ce and Li, Xian-hua and Li, Wu-xian and Li, Zheng-Xiang. 2009. Variable involvements of mantle plumes in the genesis of mid-Neoproterozoic basaltic rocks in South China: A review. Gondwana Research. 15 (3-4): pp. 381-395.
    Source Title
    Gondwana Research
    DOI
    10.1016/j.gr.2008.08.003
    ISSN
    1342937X
    Faculty
    Department of Applied Geology
    Faculty of Science and Engineering
    WA School of Mines
    Remarks

    The link to the journal’s home page is: http://www.gondwanaresearchonline.com/General/Index.aspx Copyright © 2009 Elsevier B.V. All rights reserved

    URI
    http://hdl.handle.net/20.500.11937/7034
    Collection
    • Curtin Research Publications
    Abstract

    Ca. 825-720 Ma global continental intraplate magmatism is generally linked to mantle plumes or a mantle superplume that caused rifting and fragmentation of the supercontinent Rodinia. Widespread Neoproterozoic igneous rocks in South China are dated at ca. 825-760 Ma. There is a hot debate on their petrogenesis and tectonic affiliations, i.e., mantle plume/rift settings or collision/arc settings. Such competing interpretations have contrasting implications to the position of South China in the supercontinent Rodinia and in Rodinia reconstruction models. Variations in the bulk-rock compositions of primary basaltic melts can provide first order constraints on the mantle thermal-chemical structure, and thus distinguish between the plume/rift and arc/collision models. Whole-rock geochemical data of 14 mid-Neoproterozoic (825-760 Ma) basaltic successions are reviewed here in order to (1) estimate the primary melts compositions; (2) calculate the melting conditions and mantle potential temperature; and (3) identify the contributions of subcontinental lithosphere mantle (SCLM) and asenthospheric mantles to the generation of these basaltic rocks. In order to quantify the mantle potential temperatures and percentages of decompression melting, the primary MgO, FeO, and SiO2 contents of basalts are calculated through carefully selecting less-evolved samples using a melting model based on the partitioning of FeO and MgO in olivine. The mid-Neoproterozoic (825-760 Ma) potential temperatures predicted from the primary melts range from 1390 C to 1630 C (mostly N1480 C), suggesting that most 825-760 Ma basaltic rocks in South China were generated by melting of anomalously hot mantle sources with potential temperatures 80-200 C higher than the ambient Middle Ocean Ridge Basalt (MORB)-source mantle.The mantle source regions of these Neoproterozoic basaltic rocks have complex histories and heterogeneous compositions. Enriched mantle sources (e.g., pyroxenite and eclogite) are recognized as an important source for the Bikou and Suxiong basalts, suggesting that their generations may have involved recycled components. Trace elements variations show that interactions between asthenospheric mantle (OIB-type mantle) and SCLM played a very important role in generation of the 825-760 Ma basalts. Our results indicate that the SCLM metasomatized by subduction-induced melts/fluids during the 1.0-0.9 Ga orogenesis as a distinct geochemical reservoir that contributed significantly to the trace-elements and isotope inventory of these basalts.The continental intraplate geochemical signatures (e.g., OIB-type), high mantle potential temperatures and recycled components suggest the presence of a mantle plume beneath the Neoproterozoic South China block. We use the available data to develop an integrated plume-lithosphere interaction model for the ca. 825-760Ma basalts. The early phases of basaltic rocks (825-810 Ma) were most likely formed by melting within the metasomatized SCLM heated by the rising mantle plume. The subsequent continental rift allowed adiabatic decompression partial melting of an upwelling mantle plumes at relatively shallow depth to form the widespread syn-rifting basaltic rocks at ca. 810-800 Ma and 790-760 Ma.

    Related items

    Showing items related by title, author, creator and subject.

    • The Tongde Picritic Dikes in the Western Yangtze Block: Evidence for Ca. 800-Ma Mantle Plume Magmatism in South China during the Breakup of Rodinia
      Li, X.; Zhu, W.; Zhong, H.; Wang, Xuan-Ce; He, D.; Bai, Z.; Liu, F. (2010)
      Secondary ion mass spectroscopy U-Pb zircon ages and mineralogical, geochemical, and Nd isotopic data are reported for the Tongde picritic dikes in the Yanbian area of the western Yangtze Block, South China. The picritic ...
    • Ca. 825 Ma komatiitic basalts in South China: First evidence for >1500 degrees C mantle melts by a Rodinian mantle plume
      Wang, X.; Li, X.; Li, W.; Li, Zheng-Xiang (2007)
      Mantle plume or superplume activities have repeatedly been invoked as a cause for the breakup of the Neoproterozoic supercontinent Rodinia, with supportive evidence including radiating dike swarms, globally synchronous ...
    • Initial breakup of supercontinent Rodinia as recorded by ca 860–840 Ma bimodal volcanism along the southeastern margin of the Yangtze Block, South China
      Lyu, P.; Li, W.; Wang, Xuan-Ce; Pang, C.; Cheng, J.; Li, X. (2017)
      Abstract It is considered that mantle plumes play an important role in the breakup of supercontinents, but continental rifting and associated bimodal volcanism often predate mantle-plume magmatism and the major stage of ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.