Publication Details

Fergusson, C. L., Henderson, R. A. & Offler, R. (2017). Late Neoproterozoic to early Mesozoic sedimentary rocks of the Tasmanides, eastern Australia: provenance switching associated with development of the East Gondwana active margin. In R. Mazumder (Ed.), Sediment Provenance: Influences on Compositional Change from Source to Sink (pp. 325-369). Netherlands: Elsevier.


The Tasmanides in eastern Australia are the most widely exposed part of the East Gondwana Paleozoic active margin assemblage. Diverse sedimentary assemblages are abundant and include: (1) extensive quartz-rich turbidites and shallow marine to fluvial successions, (2) continental margin and island arc derived sedimentary successions with abundant volcanic lithic detritus, and (3) widespread deep-marine to subaerial successions formed from reworking of older rocks. Apart from island arcs such as the Devonian Gamilaroi-Calliope Arc, most of the Tasmanides sedimentary assemblages formed along or in close proximity to the Gondwana margin. We highlight the interplay and provenance switching between the development of igneous dominated detritus related to adjoining magmatic arcs, such as the Macquarie Arc, and interactions with Gondwana derived sedimentary successions. Paleocurrents and detrital zircon ages indicate periodic influxes of mainly quartz-rich sand derived from the East Gondwana margin and adjacent interior with a common Pacific-Gondwana detrital zircon age signature (600-500 Ma), especially in the Cambrian, Early to Middle Ordovician, and Middle Triassic. A major quartzose turbidite deposit formed in an oceanic setting was accreted to the northern New England accretionary complex in the Late Carboniferous. This contrasts with the bulk of the Devonian to Carboniferous succession of the southern New England Orogen, which is dominated by volcaniclastic input with minor Gondwana-derived detritus. Surprisingly, even the base of the intraoceanic Macquarie Arc shows detrital zircon ages indicative of Gondwana input. The prevalence of Gondwana clastic input into the Tasmanides shows that much of the orogenic belt developed in an active continental margin setting with limited strike-slip displacements, and apart from offshore island arcs, lacks exotic terranes.