Document Type

Article

Publication Title

Tectonics

Publication Date

11-25-2003

First Page

1068

Issue Number

6

Volume Number

22

Abstract/ Summary

Contraction, strike slip, and extension displacements along the Hikurangi margin northeast of the North Island of New Zealand coincide with large lateral gradients in material properties. We use a finite- difference code utilizing elastic and elastic-plastic rheologies to build large- scale, three-dimensional numerical models which investigate the influence of material properties on velocity partitioning within oblique subduction zones. Rheological variation in the oblique models is constrained by seismic velocity and attenuation information available for the Hikurangi margin. We compare the effect of weakly versus strongly coupled subduction interfaces on the development of extension and the partitioning of velocity components for orthogonal and oblique convergence and include the effect of ponded sediments beneath the Raukumara Peninsula. Extension and velocity partitioning occur if the subduction interface is weak, but neither develops if the subduction interface is strong. The simple mechanical model incorporating rheological variation based on seismic observations produces kinematics that closely match those published from the Hikurangi margin. These include extension within the Taupo Volcanic Zone, uplift over ponded sediments, and dextral contraction to the south.

Citation/Publisher Attribution

Upton, P, Koons, PO, and Eberhart-Phillips, D, 2003, Extension and Partitioning in an Oblique Subduction Zone, New Zealand: Constraints from Three-Dimensional Numerical Modeling: Tectonics, v. 22, p. 1068. To view the published open abstract, go to http://dx.doi.org and enter the DOI.

Publisher Statement

© Copyright 2003 American Geophysical Union

DOI

10.1029/2002TC001431

Version

publisher's version of the published document

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