Chemical U-Th-Pb monazite dating of the Cambrian Tyennan Orogeny, Tasmania

Chemical U-Th-Pb dating of monazite from 12 schists throughout western and central Tasmania define a peak metamorphic age of ca 510 Ma. This age is very close to the age of arc-continent collision and ophiolite emplacement, implying very rapid uplift and cooling. To the south, along the western marg...

Full description

Bibliographic Details
Published in:Australian Journal of Earth Sciences
Main Authors: Berry, RF, Chmielowski, RM, Steele, DA, Meffre, S
Format: Article in Journal/Newspaper
Language:English
Published: Taylor & Francis 2007
Subjects:
Earth Sciences
Geology
Geochronology
South Tasman Rise
Antarc*
Antarctica
Online Access:https://doi.org/10.1080/08120090701305269
http://ecite.utas.edu.au/51584
Description
Summary:Chemical U-Th-Pb dating of monazite from 12 schists throughout western and central Tasmania define a peak metamorphic age of ca 510 Ma. This age is very close to the age of arc-continent collision and ophiolite emplacement, implying very rapid uplift and cooling. To the south, along the western margin of the South Tasman Rise, metamorphism occurred later at 495 Ma, which correlates with a late stage of the Ross Orogeny, Antarctica. The Tyennan Orogeny in Tasmania has a three-stage history similar in age to the Delamerian Orogeny in South Australia. However, the Tyennan Orogeny only produced metamorphic rocks during the early stage associated with ophiolite obduction at 515-505 Ma. The intense compressional event recognised in the Delamerian and Ross Orogeny at 500-495 Ma is correlated with a mild basin inversion in Tasmania, and no metamorphism on mainland Tasmania has been recognised associated with this event. The western margin of the South Tasman Rise is a fragment of the Ross Orogen and does not correlate directly with Tasmania.

Similar Items