Publication Name: Eastern Australian Basins Symposium 2001
Authors: M. Sdrolias, R.D. M?ller and C. Gaina
Date Published: November 2001
Number of Pages: 34
Reference Type: Magazine Article
Abstract:
An important component in the interpretation and assessment of a hydrocarbon exploration target is an accurate and self-consistent plate kinematic reconstruction of the region of interest. Identifying changes in tectonic regime assists in the analysis of associated structures, stratigraphy, subsidence/uplift and thermal anomalies. This study presents a regional tectonic model for eastern Australian marginal basins -an area of potential deep-water hydrocarbon exploration particularly in the Lord Howe Rise and Norfolk Basin region - based upon marginal basin formation, plate circuit closure and geological data. Convergence between the Pacific and Australian plates occurred between 120-100 Ma and was succeeded by active extension/transtension associated with the break-up of continental East Gondwana. Convergence resumed between the Pacific and Australian plate along the Loyalty-Three Kings Ridge at -90 Ma until its cessation at 45 Ma and was ontemporaneous with the opening of the Tasman Sea. Subsequently, a jump in subduction to the east was initiated along a westward-dipping subduction system at -45 Ma. Trench roll-back caused the opening of the North Loyalty Basin (45-35 Ma), the Norfolk Basin (45-35 Ma) and movement along the Cook Fracture Zone. Back-arc basin formation then transferred to the South Fiji Basin between 35-25 Ma and formed as two contemporaneous triple junctions. The South Fiji Basin ceased forming at -25 Ma in response to a major plate reorganisation. A lull in basin formation throughout most of the Miocene was followed by recent back-arcspreading in the Lau Basin and back-arc rifting in the Havre Trough.