Wrench tectonics flip at oblique subduction. A model from New Zealand

Abstract

In eastern North Island New Zealand, oblique subduction of the Pacific Plate beneath the Australian Plate is associated with strain partitioning. Dextral along-strike component of displacement occurred first at Early Miocene major faults within the eastern fore-arc domain. These faults were active from Early Miocene to Pliocene times. Since Pliocene times most of the movement occurs at western faults such as the Wellington Fault. The latter joins the back-arc domain to the north. The jump of wrench faulting is related with the oblique opening of the backarc domain. Both phenomena are impeded southwards by the Hikurangi oceanic plateau entering the subduction zone.

Seismicity and state of stress within the overriding plate of the Tonga‐Kermadec subduction zone

“…In this computation, the Havre Trough opening rate was neglected owing to its small magnitude and the uncertainty of its present‐day back‐arc opening. However, if we compare the direction normal to the extensional structures within the Havre Trough to the convergence direction of the Pacific Plate [ Delteil et al , 2003], the consideration of the mean inferred Havre Trough opening rate of 17 mm/yr would tend to decrease the margin‐parallel motion, suggesting that the slip partitioning would be mostly accommodated within the back‐arc domain. In the Tonga segment, the margin‐parallel motion of the Tonga arc block was estimated using the GPS plate velocity vectors between the Pacific and the Tonga arc plates [ Bevis et al , 1995] and thus the Lau Basin opening is taken into account in the computation of the slip partitioning.…”

“…The southern end of the studied area corresponds to the Taupo volcanic zone in the North Island of New Zealand, which is interpreted as an active back‐arc basin undergoing consequently normal faulting [ Parson and Wright , 1996]. This complex region is controlled by the oblique subduction of the Hikurangi plateau and farther south, around 44°S, by the Chatham Rise [ Herzer et al , 2000; Delteil et al , 2003]. These oceanic plateaus induce a strong interplate coupling between the two plates as evidenced by the large seismic gap.…”

Episodicity of Mesozoic terrane accretion along the Pacific margin of Gondwana: implications for superplume-plate interactions

“…In particular, superimposed on the pre-rift (Laird & Bradshaw 2004) terrane complexity described by Bradshaw (1989) and Mortimer (2004) is the large-scale, ~460 km (Sutherland et al 2000), Cenozoic movement of the Alpine Fault (Norris et al 1990). The fault is a distributed strike-slip transfer zone (Hall et al 2004) between east-directed subduction to the south (Norris & Cooper 2003) and west directed subduction to the north (Delteil et al 2003) and illustrates that the expression of plate boundary forces is not necessarily straightforward. In this context, the plate boundary forces, changes in subduction rate, potential slab capture, and collision of the Hikurangi Plateau, all of which combined to drive mid-Cretaceous deformation in New Zealand may have been expressed in different but co-existing ways.…”

The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt

“…The angle of 82° exists between convergent direction and plate boundary. Motion of Luonan-Luanchuan convergent belt is subduction and sinistral strike-slip, similar to the convergent mode of many orogenic belts in the world [13][14][15][16][17][18][19][20][21][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47] .…”