Basement structure and its influence on the pattern and geometry of continental rifting and breakup along Australia's southern rift margin  


Authors / CoAuthors

Gibson, G.M. | Totterdell, J.M. | Morse, M.P. | Goncharov, A. | Mitchell, C.H. | Stacey, A.R.

Abstract

Palaeogeographic reconstructions of the Australian and Antarctic margins based on matching basement structures are commonly difficult to reconcile with those derived from ocean floor magnetic anomalies and plate vectors. Following identification of a previously unmapped crustal-scale structure in the southern part of the Delamerian Orogen (Coorong Shear Zone), a revised plate reconstruction for these margins is proposed. This reconstruction positions the Coorong Shear Zone opposite the Mertz Shear Zone and indicates that structural inheritance had a profound influence on the location and geometry of continental breakup, and ocean fracture development. Previously, the Mertz Shear Zone has been correlated with the Proterozoic Kalinjala Mylonite Zone in the Gawler craton but this means that Australia is positioned 300-400 km too far east relative to Antarctica prior to breakup. Differences in the orientation of late Jurassic-Cretaceous basin-bounding normal faults in the Bight and Otway basins further suggest that extensional strain during basin formation was partitioned across the Coorong Shear Zone following an earlier episode of strike-slip faulting on a northwest-striking continental transform fault (Trans-Antarctic Shear).

Product Type

document

eCat Id

74031

Contact for the resource

  Custodian

ED  

  Owner

Commonwealth of Australia (Geoscience Australia)  

  Custodian

Commonwealth of Australia (Geoscience Australia)  
Cnr Jerrabomberra Ave and Hindmarsh Dr GPO Box 378
Canberra
ACT
2601
Australia

Keywords

  • GA PublicationRecord
( Theme )
  • continental margins
( Theme )
  • palaeogeography
( Theme )
  • tectonic history
( Theme )
  • structural geology
( Theme )
  • Antarctic data
Australian and New Zealand Standard Research Classification (ANZSRC)
  • Earth Sciences
  • Published_External

Publication Date

2012-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - license

Use - license

Status

Purpose

Maintenance Information

unknown

Topic Category

geoscientificInformation

Series Information

Record 2012/047

Lineage

Unknown

Parent Information

Extents

Reference System

Spatial Resolution

Service Information

Associations

Downloads and Links

Download the Record (pdf)  

Source Information

Source data not available.