Abstract

The island of Tasmania in southeast Australia has a number of geological elements. The relationship between these elements is largely obscured by younger cover of the Tasmania Basin, including extensive dolerites which limit the ability of potential field techniques to map basement. Therefore the development of a robust tectonic model for Tasmania has been inhibited. A seismic program was undertaken to map the large scale structure of Tasmania at depth. Deep seismic profiles were collected offshore along the entire coastline; the airguns were also recorded at a number of seismographs deployed across the island, allowing low resolution 3D tomographic imaging. Short reflection profiles were also recorded onshore across structures which could not be imaged by the offshore profiling. The Proterozoic basement in the northwest and in the Tyennan Block in the core of the island is unreflective, except for mostly east dipping reflectors which project to the surface at block boundaries. In the east, however, the lower crust is broken into rotated blocks whose boundary faults are reflective, indicating progressively greater crustal extension of the Tyennan Block to the northeast, where a reflective lower crust is interpreted to be highly extended continental crust with passive margin sediments and possibly fragments of oceanic crust. The apparently complex geology of Tasmania therefore fits into a Simple tectonic model in which several episodes of crustal extension occurred before oceanic crust formed to the northeast. The extended crust has now been inverted, probably from the northeast.
Google map showing geographic bounding box with values North bound -40.0 East bound 150.0 West bound 144.0 South bound -44.0

Product Type/Sub Type

nonGeographicDataset

Constraints

Creative Commons Attribution 4.0 International Licence

IP Owner

Commonwealth of Australia (Geoscience Australia)

Author(s)

Date (publication)

1998-01-01T00:00:00

Product Type

nonGeographicDataset

Topic Category

geoscientificInformation

GA Catalogue Number

71062 Product http://www.ga.gov.au/metadata-gateway/metadata/record/71062/

Keywords

External Publication
Scientific Journal Paper
AU-TAS
Earth Sciences

Resource Language

English

Resource Character Set

utf8

Resource Security Classification

unclassified

Geographic Extent

North bound
-40.0
East bound
150.0
West bound
144.0
South bound
-44.0

Lineage

Unknown

Digital Transfer Options

onLine

Distributor

Role
distributor
Organisation Name
Commonwealth of Australia (Geoscience Australia)
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address

Source Description

Source data not available.

Metadata File Identifier

a05f7892-f99c-7506-e044-00144fdd4fa6

Metadata Standard Name

ANZLIC Metadata Profile: An Australian/New Zealand Profile of AS/NZS ISO 19115:2005, Geographic information - Metadata

Metadata Standard Version

1.1

METADATA SECURITY CLASSIFICATION

unclassified

Metadata Contact

Role
pointOfContact
Organisation Name
Commonwealth of Australia (Geoscience Australia)
City
Canberra
Administrative Area
ACT
Postal Code
2601
Country
Australia
Email Address