eCite Digital Repository

Mesoproterozoic Tasmania: witness to the East Antarctica-Laurentia connection within Nuna

Citation

Mulder, JA and Halpin, JA and Daczko, NR, Mesoproterozoic Tasmania: witness to the East Antarctica-Laurentia connection within Nuna, Geology, 44, (3) pp. e383. ISSN 0091-7613 (2016) [Letter or Note in Journal]


Preview
PDF
Pending copyright assessment - Request a copy
126Kb
  

DOI: doi:10.1130/G37740Y.1

Abstract

Our detrital zircon U-Pb-Hf isotopic data and paleocurrent indicators from the lower-middle Rocky Cape Group (RCG) of northwest Tasmania, a >10-km-thick package of marine sedimentary rocks, are consistent with a provenance including basement terranes in the southern Mawson continent (East Antarctica) and southwest Laurentia, supporting a SWEAT-like configuration for the supercontinent Nuna between 1.45 and 1.3 Ga (Mulder et al., 2015). Moore and Betts (2016) challenge our proposed paleogeographic position for Tasmania within Nuna. Instead, they champion an alternative position for Proterozoic Tasmania that they claim better fits elements of Tasmanian geology outside of the RCG (Moore et al., 2015). From the outset, we would like to reiterate that the data and paleogeographic reconstruction presented us were discussed in the context of the Nuna supercontinent and based on the most recent reconstruction by Pisarevsky et al. (2014). We specifically addressed the interval 1.45– 1.3 Ga, which encompasses the period in which Nuna started to rift and break apart. Nowhere do we address the reconstructed position of VanDieland—a microcontinent that includes rocks as young as Cambrian, and represents Tasmania (and central Victoria, South Tasman Rise, and East Tasman Plateau) just prior to incorporation into Gondwana (Cayley, 2011). Although most of the points raised by Moore and Betts are not directly relevant to the dataset and reconstruction in our paper, we welcome the opportunity to elaborate on our ongoing research on the Proterozoic tectonics of Tasmania by addressing the issues they have raised.

Item Details

Item Type:Letter or Note in Journal
Keywords:Nuna, Rodina, Rocky Cape Group, zircon
Research Division:Earth Sciences
Research Group:Geology
Research Field:Tectonics
Objective Division:Expanding Knowledge
Objective Group:Expanding Knowledge
Objective Field:Expanding Knowledge in the Earth Sciences
Author:Mulder, JA (Mr Jacob Mulder)
Author:Halpin, JA (Dr Jacqueline Halpin)
ID Code:107119
Year Published:2016
Deposited By:IMAS Research and Education Centre
Deposited On:2016-03-04
Last Modified:2016-03-07
Downloads:1 View Download Statistics

Repository Staff Only: item control page