Structural history and tectonics of the Palaeozoic Shoalwater and Wandilla terranes, northern New England Orogen, Queensland

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Abstract
The New England Orogen of coastal central Queensland contains the Wandilla terrane in the west and the Shoalwater terrane in the east and north. Both terranes underwent multiple deformation (D1‐D4) and at least one main episode of prolonged metamorphism. The first deformation (D1) resulted from subduction accretion in a Devonian and Carboniferous forearc. Early subduction complex structures in the Wandilla terrane are dominated by steeply dipping melange with lenticular phacoids of tuff and greywacke in a mudstone matrix; whereas in the Shoalwater terrane strata are mainly coherent and the overall structure is inferred to comprise slices repeated by an imbricate thrust system. The second deformation (D2) is widespread in both terranes and formed a mostly subhorizontal to moderately east‐dipping cleavage and tight to open F2 folds. A strong down‐dip stretching lineation was generated in the Wandilla terrane. F2 folds and S0‐S2 relationships have a consistent geometry indicating an antiform to the east. Rotation of bedding, already steeply dipping due to subduction accretion, resulted in overturned strata that are typical of the Shoalwater terrane. D3 and D4 developed as a progressive sequence during the same general deformation as D2; this occurred in the Middle to Late Permian although farther west its effects continued into the Triassic.