Fold-interference patterns in the Bowen Basin, northeastern Australia

ABSTRACT

Deformation patterns of Paleozoic and Mesozoic strata in eastern Australia are evidence of a structural and tectonic history that included multiple periods of deformation with variable strain intensities and orientations. Detailed analysis of structural data from the Bowen Basin in northeastern Australia reveals previously undescribed, north–south elongate, Type-1 fold-interference patterns. The Bowen Basin structures have similar orientations to previously described interference patterns of equivalent scale in upper Paleozoic strata of the New England Orogen and Sydney Basin of eastern Australia. The east Australian folds with north–south-trending axes most likely formed during late stages of the Permian–Triassic Hunter–Bowen Orogeny, and they were subsequently refolded around east–west axes during post 30 Ma collision of the Indo-Australian plate with the Eurasian and Pacific plates. The younger, east–west-trending folds have orientations that are well aligned with the present-day horizontal stress field of much of eastern Australia, raising the possibility that they are active structures.

KEYWORDS:

• fold-interference patterns
• Bowen Basin
• New England Orogen
• eastern Australia
• Hunter–Bowen Orogeny

Acknowledgements

The paper benefited from helpful and insightful comments by Joan Esterle, Peter Betts, Caroline Forbes and an anonymous reviewer.

Disclosure statement

No potential conflict of interest was reported by the authors.