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

    Pan-African granulites of Madagascar and southern India: Gondwana assembly and parallels with modern Tibet

    Access Status
    Open access via publisher
    Authors
    Fitzsimons, Ian
    Date
    2016
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Fitzsimons, I. 2016. Pan-African granulites of Madagascar and southern India: Gondwana assembly and parallels with modern Tibet. Journal of Mineralogical and Petrological Sciences. 111 (2): pp. 73-88.
    Source Title
    Journal of Mineralogical and Petrological Sciences
    DOI
    10.2465/jmps.151117
    ISSN
    1345-6296
    School
    Department of Applied Geology
    URI
    http://hdl.handle.net/20.500.11937/36237
    Collection
    • Curtin Research Publications
    Abstract

    Granulites of the southern East African Orogen formed by continental collision during Gondwana assembly. The highest metamorphic gradients of 25-50°C km-1 were attained at 0.58-0.53 Ga in a microcontinental block that was sandwiched between two collisional sutures and is now exposed in Madagascar and southern India. The 50 Myr duration of extreme pressure-temperature (P-T) conditions and lack of coeval mantle magmatism suggest that metamorphism was driven by radiogenic heat accumulation beneath a long-lived orogenic plateau. Bounding sutures most likely record transfer of this microcontinent across the Neoproterozoic Mozambique Ocean, analogous to Gondwanan terranes that crossed Tethys before final India-Asia collision and, like Tibet, these sutures mark the edges of a plateau that formed following terminal ocean closure and collision. Both sutures record moderate metamorphic gradients of 15-25°C km-1 but with quite different ages. Metamorphism along the western suture at 0.65-0.61 Ga followed the end of magmatism in an adjacent 0.85-0.65 Ga ocean-arc terrane. It has an anti-clockwise P-T path that reflects preferential thickening of the hot arc during early stages of collision, and dates ocean closure at the western suture. Metamorphism along the eastern suture at 0.53-0.51 Ga has a clockwise P-T path and is widely assumed to date terminal collision in the East African Orogen. However, this event was coeval with rapid exhumation of granulites in the adjacent plateau and is more likely to reflect reactivation of a much older eastern suture during plateau collapse. Great care should be taken when using metamorphism to date ocean closure in ancient orogens. Rocks with hot metamorphic gradients give poor age constraints on initial collision because peak T is attained >50 Myr after ocean closure if radioactivity is a major part of the heat budget. Suture zone rocks with moderate metamorphic gradients can provide more reliable estimates for the time of ocean closure but are also prone to later reactivation in orogens with protracted histories.

    Related items

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

    • The timing of final closure along the Changchun-Yanji suture zone: Constraints from detrital zircon U-Pb dating of the Triassic Dajianggang Formation, NE China
      Wang, B.; Zhou, J.; Wilde, Simon; Zhang, X.; Ren, S. (2015)
      © 2015 Elsevier B.V. The Dajianggang Formation is located in the Changchun-Yanji suture zone of central Jilin Province and unconformably overlies the Changchun-Yanji Accretionary Complex (CYAC), which is a mélange resulting ...
    • New Crustal Vs Model Along an Array in South-East China: Seismic Characters and Paleo-Tethys Continental Amalgamation
      Li, T.; Zhao, L.; Wan, B.; Li, Zheng-Xiang ; Bodin, T.; Wang, K.; Yuan, H. (2020)
      The assembly of East Asia was closely linked to the closure of the Tethyan oceans. In south-east China, the closure of the Paleo-Tethys ocean led to a continental collision between the South China and North China blocks ...
    • Formation of a Composite Albian–Eocene Orogenic Wedge in the Inner Western Carpathians: P–T Estimates and 40Ar/39Ar Geochronology from Structural Units
      Putiš, M.; Nemec, O.; Danišík, Martin ; Jourdan, Fred ; Soták, J.; Tomek, Č.; Ružička, P.; Molnárová, A. (2021)
      The composite Albian–Eocene orogenic wedge of the northern part of the Inner Western Carpathians (IWC) comprises the European Variscan basement with the Upper Carboniferous–Tri-assic cover and the Jurassic to Upper ...
    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.