Fragmented Tasmania: The transition from Rodinia to Gondwana

David Hugh Moore, Peter Graham Betts, Walter David Michael Hall

Research output: Contribution to journalArticleResearchpeer-review

27 Citations (Scopus)

Abstract

The origin of the microcontinent VanDieland extends back to the late Paleoproterozoic, where it was positioned between East Antarctica and southwestern Laurentia, within the supercontinent Nuna and Rodinia. Paleo- to Mesoproterozoic events recorded in VanDieland have greater affinities with southwest Laurentia and East Antarctica, suggesting southern VanDieland was part of the Grenville Front, and the central Tasmanian part was adjacent to the Miller Range in the central Transantarctic Mountains. Late in the Neoproterozoic Rodinia break-up, VanDieland separated from East Antarctica and southwestern Laurentia, and moved north along the Terra Australis margin until its southern part was positioned next to the easternmost Robertson Bay Terrane of north Victoria Land. VanDieland comprises up to seven different crustal megaboudins or microcontinental ribbon terranes that likely had amalgamated by the end of the Cambrian; these ribbon terranes are bounded by major faults and suture zones. Some boundaries, such as the Arthur Metamorphic Complex, are well known. However, other boundaries, like the eastern edge of the Tyennan Zone, and the boundary between King Island and northwestern Tasmania, are more cryptic, as they are covered by younger geology or are under water. The boundaries are commonly defined by sedimentary and mafic volcanic infill that has been trapped between the crustal fragments. These rocks have previously been interpreted as allochthonous terranes but are more likely to represent inverted sections of attenuated transitional crust and back arc basin fill that formed along the eastern margin of the Gondwana plate during the Cambrian.
Original languageEnglish
Pages (from-to)1 - 35
Number of pages35
JournalAustralian Journal of Earth Sciences
Volume62
Issue number1
DOIs
Publication statusPublished - 2015

Cite this