Structural Architecture of Australia's 4000 km-long Southern Rifted Continental Margin  

Authors / CoAuthors

Totterdell, J.M. | Gibson, G.M. | Stacey, A.R. | Mitchell, C.H. | Morse, M.J. | Nayak, G.K.

Abstract

Many aspects of the evolution and overall architecture of the Australian southern rifted margin are consistent with current models for the development of non-volcanic rifted margins. However, when examined in detail, several key features of the southern margin provide useful points of comparison with the Atlantic and Alpine Tethyan margins from which these models derive. Extensive petroleum industry and government seismic and geophysical data sets have enabled detailed mapping of the basins of the southern margin and an improved understanding of its tectonostratigraphic evolution. Australia's southern rifted continental margin extends for over 4000 km, from the structurally complex margin south of the Naturaliste Plateau in the west, to the transform plate boundary adjacent to the South Tasman Rise in the east. The margin contains a series of Middle Jurassic to Cenozoic basins-the Bight, Otway, Sorell, Gippsland and Bass basins, and smaller depocentres on the South Tasman Rise (STR). These basins, and the architecture of the margin, evolved through repeated episodes of extension and thermal subsidence leading up to, and following, the commencement of sea-floor spreading between Australia and Antarctica. Break-up took place diachronously along the margin, commencing in the west at ~83 Ma and concluding in the east at ~ 34 Ma. In general, break-up was not accompanied by significant magmatism and the margin is classified as 'non-volcanic' (or magma-poor). Initial NW-SE ultra-slow to slow seafloor spreading (latest Santonian-Early Eocene), followed by N-S directed fast spreading (Middle Eocene-present), resulted in: (1) an E-W oriented obliquely- to normally-rifted marginal segment extending from the westernmost Bight Basin to the central Otway Basin; (2) an approximately N-S oriented transform continental margin in the east (western Tasmania-STR), and (3) a transitional zone between those end-members (southern Otway-Sorell basins).

Product Type

nonGeographicDataset

eCat Id

71392

Contact for the resource

Keywords

• External PublicationAbstract

( Theme )

• continental margins

( Theme )

• sedimentary basins

( Theme )

• structural geology

Australian and New Zealand Standard Research Classification (ANZSRC)

• Earth Sciences

• Published_Internal

Publication Date

2011-01-01T00:00:00

Creation Date

Security Constraints

Australian Government Security ClassificationSystem    

Classification - unclassified

Legal Constraints

Creative Commons Attribution 4.0 International Licence    

Access - restricted

Use - license

Status

Purpose

Maintenance Information

unknown

Topic Category

geoscientificInformation

Series Information

Lineage

Unknown

Parent Information

Extents

Reference System

Spatial Resolution

Service Information

Associations

Downloads and Links

Source Information

Source data not available.