Journal ArticleDOI
Structure of a growing accretionary prism, Hikurangi margin, New Zealand
TLDR
The Hikurangi margin of eastern North Island, New Zealand, represents the feather edge of the Indian plate at its convergent boundary with the subducting Pacific plate, and a migrated seismic reflection profile across this margin clearly displays the structural evolution of an accretionary prism as discussed by the authors.Abstract:
The Hikurangi margin of eastern North Island, New Zealand, represents the feather edge of the Indian plate at its convergent boundary with the subducting Pacific plate. A migrated seismic reflection profile across this margin clearly displays the structural evolution of an accretionary prism. A 25-km-wide band of “protothrusts” is delineated between the toe of the slope and a converging seamount; this illustrates an early stage in the seaward propagation of a deformation front. Landward-tilted trench-slope basins are separated by ridges that have clearly defined thrusts, which appear to sole out at a decollement. The decollement continues at an angle of only 3° beneath the 150-km-wide margin to a depth of 14 km near the coast where it coincides with an onshore zone of high seismicity.read more
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Spontaneous and triggered aseismic deformation transients in a subduction fault model
TL;DR: In this paper, the authors show that if interstitial fluids are present and pore pressure is near-lithostatic around and downdip from the frictional stability transition, transients with recurrence intervals of ∼1 year are predicted on the basis of laboratory friction parameters and their temperature (hence depth) variations.
Journal ArticleDOI
Tectonic and geological framework for gas hydrates and cold seeps on the Hikurangi subduction margin, New Zealand
Philip M. Barnes,Geoffroy Lamarche,Jörg Bialas,Stuart Henrys,Ingo Pecher,G L Netzeband,Jens Greinert,Joshu J. Mountjoy,Joshu J. Mountjoy,K. Pedley,Gareth Crutchley +10 more
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Geochemical Evolution within the Tonga–Kermadec–Lau Arc–Back-arc Systems: the Role of Varying Mantle Wedge Composition in Space and Time
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Isotopic composition of helium, and CO2 and CH4 contents in gases produced along the New Zealand part of a convergent plate boundary
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Ambient Noise Rayleigh Wave Tomography of New Zealand
TL;DR: In this article, the authors present the first New Zealand-wide study of surface wave dispersion, using ambient noise observed at 42 broad-band stations in the national seismic network (GeoNet) and the Global Seismic Network (GSN).