Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Letter
  • Published:

Fluid and deformation regime of an advancing subduction system at Marlborough, New Zealand


Newly forming subduction zones on Earth can provide insights into the evolution of major fault zone geometries from shallow levels to deep in the lithosphere and into the role of fluids in element transport and in promoting rock failure by several modes1,2. The transpressional subduction regime of New Zealand, which is advancing laterally to the southwest below the Marlborough strike–slip fault system of the northern South Island3,4, is an ideal setting in which to investigate these processes. Here we acquired a dense, high-quality transect of magnetotelluric soundings across the system, yielding an electrical resistivity cross-section to depths beyond 100 km. Our data imply three distinct processes connecting fluid generation along the upper mantle plate interface to rock deformation in the crust as the subduction zone develops. Massive fluid release just inland of the trench induces fault-fracture meshes through the crust above that undoubtedly weaken it as regional shear initiates. Narrow strike–slip faults in the shallow brittle regime of interior Marlborough diffuse in width upon entering the deeper ductile domain aided by fluids and do not project as narrow deformation zones. Deep subduction-generated fluids rise from 100 km or more and invade upper crustal seismogenic zones that have exhibited historic great earthquakes on high-angle thrusts that are poorly oriented for failure under dry conditions. The fluid-deformation connections described in our work emphasize the need to include metamorphic and fluid transport processes in geodynamic models.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Geological terrane map of central New Zealand8.
Figure 2: Nonlinear 2D inversion model of electrical resistivity below the Marlborough–northern Westland district.
Figure 3: Interpretative geological/fluidized states over pertinent depth ranges for labelled major conductive zones imaged below the magnetotelluric transect.

Similar content being viewed by others


  1. Stern, R. J. Subduction initiation: spontaneous and induced. Earth Planet. Sci. Lett. 226, 275–292 (2004)

    Article  ADS  CAS  Google Scholar 

  2. Schellart, W. P., Freeman, J., Stegman, D. R., Moresi, L. & May, D. Evolution and diversity of subduction zones controlled by slab width. Nature 446, 308–311 (2007)

    Article  ADS  CAS  Google Scholar 

  3. Walcott, R. I. Models of oblique compression: Late Cenozoic tectonics of the South Island of New Zealand. Rev. Geophys. 36, 1–26 (1998)

    Article  ADS  Google Scholar 

  4. Furlong, K. P. in Exhumation Associated with Continental Strike-Slip Fault Systems (eds Till, A. B., Roeske, S. M., Sample, J. C. & Foster, D. A.) Geol. Soc. Am. Spec. Pap. 434 1–14 (GSA, 2008)

    Google Scholar 

  5. Wesnousky, S. G. Seismicity as a function of cumulative geologic offset: some observations from southern California. Bull. Seismol. Soc. Am. 80, 1374–1381 (1990)

    Google Scholar 

  6. Davey, F. J. et al. in A Continental Boundary: Tectonics at South Island, New Zealand (eds Okaya, D., Stern, T. & Davey, F.) Geophys. Monogr. 175 47–73 (American Geophysical Union, 2007)

    Book  Google Scholar 

  7. Becken, M. et al. A deep crustal fluid channel into the San Andreas Fault system near Parkfield, California. Geophys. J. Int. 173, 718–732 (2008)

    Article  ADS  Google Scholar 

  8. Mortimer, N. New Zealand’s geological foundations. Gondwana Res. 7, 261–272 (2004)

    Article  ADS  Google Scholar 

  9. Jongens, R. Structure of the Buller and Takaka terrane rocks adjacent to the Anatoki fault, northwest Nelson, New Zealand. NZ J. Geol. Geophys. 49, 443–461 (2006)

    Article  Google Scholar 

  10. Ghisetti, F. C. & Sibson, R. H. Accommodation of compressional inversion in north-western South Island (New Zealand): old faults versus new? J. Struct. Geol. 28, 1994–2010 (2007)

    Article  ADS  Google Scholar 

  11. Heise, W. et al. Melt distribution beneath a young continental rift: the Taupo Volcanic Zone, New Zealand. Geophys. Res. Lett. 34 L14313 10.1029/2007GL029629 (2007)

    Article  ADS  CAS  Google Scholar 

  12. Jones, A. G. Imaging the continental upper mantle using electromagnetic methods. Lithos 48, 57–80 (1999)

    Article  ADS  CAS  Google Scholar 

  13. Peacock, S. M. in Inside the Subduction Factory (ed. Eiler, J.) Am. Geophys. Monogr. 138 7–22 (American Geophysical Union, 2003)

    Book  Google Scholar 

  14. Reyners, M., Eberhart-Phillips, D. & Stuart, G. The role of fluids in lower-crustal earthquakes near continental rifts. Nature 446, 1075–1079 (2007)

    Article  ADS  CAS  Google Scholar 

  15. Ogawa, Y. & Honkura, Y. Mid-crustal electrical conductors and their correlations to seismicity and deformation at Itoigawa-Shizuoka tectonic line, central Japan. Earth Planets Space 56, 1285–1292 (2004)

    Article  ADS  Google Scholar 

  16. Eberhart-Phillips, D., Chadwick, M. & Bannister, S. Three-dimensional attenuation structure of central and southern South Island, New Zealand, from local earthquakes. J. Geophys. Res. 113 B05308 10.1029/2007JB005359 (2008)

    Article  ADS  Google Scholar 

  17. Eberhart-Phillips, D. & Henderson, M. C. Including anisotropy in 3-D velocity inversion and application to Marlborough, New Zealand. Geophys. J. Int. 156, 237–254 (2004)

    Article  ADS  Google Scholar 

  18. Cox, S. F. Coupling between deformation, fluid pressures, and fluid flow in ore-producing hydrothermal systems at depth in the crust. Soc. Econ. Geol. 100th Anniv. Vol., 39–75 (2005)

  19. Bourne, S. J., England, P. C. & Parson, B. The motion of crustal blocks driven by flow in the lower lithosphere and implications for slip rates of continental strike-slip faults. Nature 391, 655–659 (1997)

    Article  ADS  Google Scholar 

  20. Wilson, C. K., Jones, C. H., Molnar, P., Sheehan, A. F. & Boyd, O. S. Distributed deformation in the lower crust and upper mantle beneath a continental strike-slip fault zone: Marlborough fault system, South Island, New Zealand. Geology 32, 837–840 (2004)

    Article  ADS  Google Scholar 

  21. Nicol, A. & Van Dissen, R. Up-dip partitioning of displacement components on the oblique-slip Clarence fault, New Zealand. J. Struct. Geol. 24, 1521–1535 (2002)

    Article  ADS  Google Scholar 

  22. Mason, D. P. M., Little, T. A. & Van Dissen, R. J. Rates of active faulting during late Quaternary fluvial terrace formation at Saxton River, Awatere fault, New Zealand. Geol. Soc. Am. Bull. 118, 1431–1466 (2006)

    Article  ADS  Google Scholar 

  23. Cox, S. F. in Fractures, Fluid Flow and Mineralization (ed. McCaffrey, K. J. W., Lonergan, L. & Wilkinson, J. J.) Geol. Soc. Lond. Spec. Pub. 155 123–140 (GSL, 1999)

    Google Scholar 

  24. Sibson, R. H. in Deformation of the Continental Crust: the Legacy of Mike Coward Geol. Soc. Lond. Spec. Publ. 272 519–532 (GSL, 2007)

    Google Scholar 

  25. Wannamaker, P. E. et al. Fluid generation and pathways beneath an active compressional orogen, the New Zealand Southern Alps, inferred from magnetotelluric data. J. Geophys. Res. 107 10.1029/2001JB000186 (2002)

  26. Patro, P. K. & Egbert, G. D. Regional conductivity structure of Cascadia: preliminary results from 3D inversion of USArray transportable array magnetotelluric data. Geophys. Res. Lett. 35 10.1029/2008GL035326 (2008)

  27. Brasse, H. & Eydam, D. Electrical conductivity beneath the Bolivian orocline and its relation to subduction processes at the South American continental margin. J. Geophys. Res. 113 10.1029/2007JB005142 (2008)

  28. Jiracek, G. R., Gonzalez, V. M., Caldwell, T. G., Wannamaker, P. E. & Kilb, D. in A Continental Boundary: Tectonics at South Island, New Zealand (eds Okaya, D., Stern, T. & Davey, F.) Geophys. Monogr. Ser. 175 75–94 (Am. Geophys. Union, 2007)

    Google Scholar 

  29. Upton, P. & Koons, P. O. in A Continental Boundary: Tectonics at South Island, New Zealand (eds Okaya, D., Stern, T. & Davey, F.) Geophys. Monogr. Ser. 175 253–270 (Am. Geophys. Union, 2007)

    Book  Google Scholar 

  30. Beavan, J., Ellis, S. & Wallace, L. in A Continental Boundary: Tectonics at South Island, New Zealand (eds Okaya, D., Stern, T. & Davey, F.) Geophys. Monogr. Ser. 175 75–94 (Am. Geophys. Union, 2007)

    Book  Google Scholar 

  31. Vozoff, K. in Electromagnetic Methods in Applied Geophysics (ed. Nabighian, M. N.)2B 641–711 (Soc. Explor. Geophys., 1991)

    Book  Google Scholar 

  32. Booker, J. R., Favetto, A. & Pomposiello, M. C. Low electrical resistivity associated with plunging of the Nazca flat slab beneath Argentina. Nature 429, 399–404 (2004)

    Article  ADS  CAS  Google Scholar 

  33. Petiau, G. & Dupis, A. Noise, temperature coefficient, and long time stability of electrodes for telluric observations. Geophys. Prospect. 28, 792–804 (1980)

    Article  ADS  Google Scholar 

  34. Wannamaker, P. E. et al. Magnetotelluric surveying and monitoring at the Coso geothermal area, California, in support of the Enhanced Geothermal Systems concept: survey parameters and initial results. Proc. Workshop Geothermal Reservoir Engr. SGP-TR-175 1–8 (Stanford University, 2004)

  35. Jones, A. G., Chave, A. D., Egbert, G., Auld, D. & Bahr, K. A comparison of techniques for magnetotelluric response function estimation. J. Geophys. Res. 94, 14201–14213 (1989)

    Article  ADS  Google Scholar 

  36. Caldwell, T. G., Bibby, H. M. & Brown, C. The magnetotelluric phase tensor. Geophys. J. Int. 158, 457–469 (2004)

    Article  ADS  CAS  Google Scholar 

  37. Wannamaker, P. E. in Three-Dimensional Electromagnetics (ed Oristaglio, M. & Spies, B.) Geophys. Devel. Ser. 7 349–374 (Soc. Explor. Geophys., 1999)

    Book  Google Scholar 

  38. Wannamaker, P. E. et al. Lithospheric dismemberment and magmatic processes of the Great Basin-Colorado Plateau transition, Utah, implied from magnetotellurics. Geochem. Geophys. Geosyst. 9 Q05019 10.1029/2007GC001886 (2008)

    Article  ADS  Google Scholar 

Download references


This research was supported by the Geophysics program of the US National Science Foundation (grant EAR0440050), and the Plate Boundary program of the New Zealand Foundation for Research, Science and Technology. W. Hales of Alpine Springs Helicopters provided an airborne transport service to remote locations of the Marlborough and Westland regions. We thank B. Freer, C. Davis and P. Thorton of the New Zealand Department of Conservation, and numerous private landholders, for permission to access site locations. Additional field assistance was given by students M. Burgess and P. Winther. Many discussions were held with D. Eberhart-Phillips, R. Sibson and P. Upton. Illustrations were finalized by D. Jensen.

Author Contributions P.E.W., T.G.C. and G.R.J. designed the experiment. The home institutions of T.G.C. and Y.O. supplied the instrumentation. T.G.C. and G.J.H. reduced the observed time series. V.M. derived the induction vectors. All authors were essential to the success of the field campaign and contributed to the interpretation and the manuscript.

Author information

Authors and Affiliations


Corresponding author

Correspondence to Philip E. Wannamaker.

Supplementary information

Supplementary Information

This file contains a Supplementary Discussion, Supplementary Data, Supplementary References and Supplementary Figures 1-13 with Legends. (PDF 1294 kb)

PowerPoint slides

Rights and permissions

Reprints and permissions

About this article

Cite this article

Wannamaker, P., Caldwell, T., Jiracek, G. et al. Fluid and deformation regime of an advancing subduction system at Marlborough, New Zealand. Nature 460, 733–736 (2009).

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI:

This article is cited by


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing