The oroclinal bend in the South Island, New Zealand

Rotation and offset of the Gondwana convergent margin in the New Zealand region following Cretaceous jamming of Hikurangi Plateau large igneous province subduction

“…The horizontal gravity‐gradient pattern, visually apparent in the horizontal gravity slope image of Figures , and based onshore on the gravity station density of Figure a, highlights major fault locations (or steep fold structures) many of which are buried and no longer active structures. Figure b highlights the generally high correlation between gravity‐gradient lineations and mapped basement fabric [ Mortimer , ]. The gravity‐gradient plots also highlight the onshore continuation of the half‐graben on either side of the Chatham Rise.…”

Post-remagnetisation vertical axis rotation and tilting of the Murihiku Terrane (North Island, New Zealand)

“…The age of oroclinal bending within these terranes as well as its relation to Alpine Fault deformation remains uncertain. A widely held view is that Cenozoic plate motion within New Zealand was accommodated across the Alpine Fault as well as in a broad zone of deformation, leading to bending of basement terranes as a result of large-scale drag (Kamp 1987;Sutherland 1999;Mortimer 2014). An alternative view is that the basement terranes were bent pre-Cenozoic and that the curvature of the terranes remained unchanged in the Cenozoic because Neogene dextral displacement on Alpine Fault occurred in a very narrow zone (Lamb et al 2016).…”

Focusing of relative plate motion at a continental transform fault: Cenozoic dextral displacement >700 km on New Zealand's Alpine Fault, reversing >225 km of Late Cretaceous sinistral motion

“…The Paleozoic to Mesozoic geological evolution of the New Zealand involved the progressive accretion of terrains along the subducting margin of Gondwana [ Mortimer , ]. Today, these terrains form linear belts, up to a few tens of km wide, that extend for 100s to >1000 km through Zealandia, although bent and dextrally offset in onshore New Zealand (Figures and ) [ Mortimer , ].…”

“…Fiordland forms a contiguous part of the New Zealand orocline (Figure a) [ Turnbull et al ., ; Mortimer , ], and cannot be treated as an allochthonous block that was displaced 100s kilometres, as was often assumed in earlier plate reconstructions in which there has been tens to hundreds of kilometres of total strike‐slip displacement on the Te Anau, Hollyford and Hauroko‐Blackmount‐Moonlight Faults (Figure a) [ King , ]. If the two sides of the New Zealand region are fitted back to the ∼45 Ma reconstruction (Figure b), then the basement terranes can only have been contiguous across the plate‐boundary at this time if they have subsequently rotated ∼90° clockwise about a vertical axis.…”