Geodynamic significance of the boundary between the Thomson Orogen and the Lachlan Orogen, northwestern New South Wales: implications for Tasmanide tectonics  

Authors / CoAuthors

Glen, R.A. | Korsch, R.J. | Costelloe, R.D. | Hegarty, R. | Saeed, A. | Poudjom Djomani, Y. | Dick, S. | Griffin, W.L.

Abstract

Interpretation of deep seismic reflection profiling coupled with forward modelling of gravity and aeromagnetic data, new zircon U-Pb age dating and the interpretation of the basement geology beneath the southern margin of the Eromanga Basin has provided insights into the southern part of the underlying Thomson Orogen and its relationship with the Lachlan Orogen to the south. Our interpretations of these data suggest that the northern Lachlan and southern Thomson orogens possessed a similar history from the mid-Late Silurian through to the Carboniferous. Major older differences, however, are suggested by the presence in the southern Thomson Orogen of relics of a possible Neoproterozoic arc, of Late Ordovician turbidites, by the geophysical evidence for crustal thickening caused by elevation of reflective lower crustal metavolcanic rocks high into the crust on a low-angle, north-dipping detachment thrust, and by old K-Ar age dates in southwestern Queensland. The seismically-imaged, north-dipping, crustal-scale Olepoloko Fault corresponds to the surface expression of Thomson-Lachlan boundary, and reflects the dip-slip and strike-slip partial reactivation and short-cutting of an older fault, which occurred in the Carboniferous, and probably also in the latest Silurian and Early Devonian.

Product Type

nonGeographicDataset

eCat Id

74707

Contact for the resource

Keywords

• External PublicationArticle

( Theme )

• seismic reflection

( Theme )

• geodynamics

( Theme )

• geochronology

Australian and New Zealand Standard Research Classification (ANZSRC)

• Earth Sciences

• Published_Internal

Publication Date

2012-10-03T00:00:00

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.