Authors / CoAuthors
Gibson, G.M. | Morse, M.P. | Ireland, T.R. | Nayak, G.
Abstract
Crustal architecture in formerly contiguous basement terranes in SE Australia, Tasmania and northern Victoria Land is a legacy of late Neoproterozoic-Cambrian subduction-related processes, culminating in formation of the Delamerian-Ross orogen. Structures of Delamerian-Ross age were subsequently reactivated during late Mesozoic-Cenozoic Gondwana breakup, strongly influencing the geometry of continental rifting and providing clues about the origins and configuration of the pre-existing basement structures. An ocean-continent transform boundary developed off western Tasmania follows the trace of an older Paleozoic strike-slip structure (Avoca-Sorell fault) optimally oriented for reactivation during final separation of Australia from Antarctica. This boundary cuts across rocks preserving an earlier record of arc-continent collision during the course of which continental crust was subducted to mantle depths and Cambrian mafic-ultramafic island arc rocks were emplaced westwards over late Neoproterozoic passive margin sequences deposited during Rodinia breakup. Following a change to transcurrent motion along the Gondwana margin, Tasmania migrated northward along the Avoca fault system. This process arrested with entry of continental crust (Selwyn block) into a subduction zone located along the Heathcote-Governor fault systems, precipitating a second collision event accompanied by south-vergent thrusting, blueschist facies metamorphism and tectonic reworking of the already accreted Cambrian arc-forearc complex and underlying passive margin sequences.
Product Type
nonGeographicDataset
eCat Id
70061
Contact for the resource
Custodian
Owner
Custodian
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia
Digital Object Identifier
Keywords
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- External PublicationArticle
- ( Theme )
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- continental margins
- ( Theme )
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- cultural boundaries
- ( Theme )
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- structural geology
- ( Theme )
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- marine
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- AU-NSWAU-TASAU-VIC
- Australian and New Zealand Standard Research Classification (ANZSRC)
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- Earth Sciences
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- Published_External
Publication Date
2010-01-01T00:00:00
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unknown
Topic Category
geoscientificInformation
Series Information
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Unknown
Parent Information
Extents
[-44.0, -28.0, 140.0, 156.0]
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