Tectonic cycles in the Strangways Metamorphic Complex, Arunta Inlier, central Australia: Geochronological evidence for exhumation and basin formation between two high-grade metamorphic events

David W. Maidment*, M. Hand, I. S. Williams

*Corresponding author for this work

    Research output: Contribution to journalArticlepeer-review

    53 Citations (Scopus)

    Abstract

    Deformation, metamorphism and magmatism during the Strangways Orogeny in the eastern Arunta Inlier of central Australia appears to be a result of plate-margin-related tectonism along the southern margin of the North Australian Craton. SHRIMP zircon dating of basement nd cover sequences in the Strangways Metamorphic Complex indicates that the Strangways Orogeny consisted of two distinct tectonothermal cycles between ca 1.79 and ca 1.71 Ga. Sedimentary protoliths of the Mt Bleechmore Granulite were deposited after ca 1.8 Ga and probably metamorphosed at ca 1.78 Ga (the Early Strangways Event). These rocks were subsequently exhumed and eroded, forming a basement on which the Ledan Package (Mendip Metamorphics, Ledan Schist and Utopia Quartzite) was deposited after ca 1.77 Ga. Metamorphic zircon overgrowths (1723 ± 9 Ma) and a pegmatite intrusion (1730 ± 4 Ma) in the Mendip Metamorphics record a second phase of deformation and metamorphism (the Late Strangways Event). The arc-like Huckitta and Inkamulla Granodiorites in the eastern Strangways Metamorphic Complex were intruded at 1762 ± 3 Ma and 1773 ± 4 Ma, respectively, suggesting that the Early Strangways Event was associated with subduction along the southern margin of the North Australian Craton. Exhumation and basin formation between the two periods of contraction was possibly a consequence of extension after the Early Strangways Event and related to A-type magmatism at ca 1.74 Go in the eastern Strangways Metamorphic Complex, Metamorphic zircon overgrowths in the Huckitta Granodiorite have an age of 332 ± 3 Ma and record a phase of relatively high-grade metamorphism towards the end of the Alice Springs Orogeny.

    Original languageEnglish
    Pages (from-to)205-215
    Number of pages11
    JournalAustralian Journal of Earth Sciences
    Volume52
    Issue number2
    DOIs
    Publication statusPublished - Apr 2005

    Fingerprint

    Dive into the research topics of 'Tectonic cycles in the Strangways Metamorphic Complex, Arunta Inlier, central Australia: Geochronological evidence for exhumation and basin formation between two high-grade metamorphic events'. Together they form a unique fingerprint.

    Cite this