Re-evaluation of conditional probability of rupture of the Wellington-Hutt Valley segment of the Wellington Fault
New information on the activity of the Wellington-Hutt Valley segment of the Wellington Fault, New Zealand, has become available from geological and modelling studies undertaken in the last several years as part of the “It’s Our Fault” project. There are now revised estimates of: 1) the timing of the most recent rupture, and the previous four older ruptures; 2) the size of single-event displacements; 3) the Holocene dextral slip rate; and 4) rupture statistics of the Wellington-Wairarapa fault-pair, as deduced from synthetic seismicity modelling. The conditional probability of rupture of this segment over the next 100 years is re-evaluated in light of this new information, assuming a renewal process framework. Four recurrence-time distributions (exponential, lognormal, Weibull and Brownian passage-time) are explored. The probability estimates take account of both data and parameter uncertainties. A sensitivity analysis is conducted, entertaining different bounds and shapes of the probability distributions of important fault rupture data and parameters. Important findings and conclusions include:
- The estimated probability of rupture of the Wellington-Hutt Valley segment of the Wellington Fault in the next 100 years is ~11% (with sensitivity results ranging from 4% to 15%), and the probability of rupture in the next 50 years is about half of that (~5%).
- In all cases, the inclusion of the new data has reduced the estimated probability of rupture of the Wellington Fault by ~50%, or more, compared to previous estimates.
Barnes, P.M., Pondard, N., Lamarche, G., Mountjoy, J., Van Dissen, R., Litchfield, N. (2008). “It’s Our Fault: active faults and earthquake sources in Cook Strait”. NIWA Client Report WLG2008-56: 36 p.
Berryman, K.R. (1990). “Late Quaternary movement on the Wellington Fault in the Upper Hutt area, New Zealand”. New Zealand Journal of Geology and Geophysics 33: 257-270.
Ellsworth, W.L., Matthews, M.V., Nadeau, R.M., Nishenko, S.P., Reasenberg, P.A., Simpson, R.W. (1999). “A physically-based earthquake recurrence model for estimation of long-term earthquake probabilities”. U.S. Geological Survey Open-File Report 99-522: 22 p.
Grapes, R. (1993). “Terrace correlation, dextral displacements, and slip rate along the Wellington Fault, North Island, New Zealand (letters to the editor)”. New Zealand Journal of Geology and Geophysics 36: 131-135.
Hagiwara, Y. (1974). “Probability of earthquake occurrence as obtained from a Weibull distribution of crustal strain”. Tectonophysics 23: 313-318.
Hecker, S., Abrahamson, N. (2002). “Characteristic fault rupture: implications for fault rupture hazard analysis”. paper presented at Pacific Earthquake Engineering Research Centre (PEER) Lifelines Research Meeting, June 24, 2002.
Langridge, R.M., Van Dissen, R., Villamor, P., Little, T. (2009). “It’s Our Fault – Wellington Fault paleoearthquake investigations: final report”. GNS Science Consultancy Report 2008/344.
Langridge, R., Van Dissen, R., Rhoades, D., Villamor, P., Little, T., Litchfield, N., Clark, K., Clark, D., (2011). “Five thousand years of surface ruptures on the Wellington fault: implications for recurrence and fault segmentation”. Bulletin of the Seismological Society of America 101 (5): in press.
Little, T.A., Van Dissen, R., Rieser, U., Smith, E.G.C., Langridge, R. (2010). “Co-seismic strike-slip at a point during the last four earthquakes on the Wellington fault near Wellington, New Zealand”. Journal of Geophysical Research 115: B05403. doi:10.1029/2009JB006589. DOI: https://doi.org/10.1029/2009JB006589
Matthews, M.V., Ellsworth, W.L., Reasenberg, P.A. (2002). “A Brownian model for recurrent earthquakes”. Bulletin of the Seismological Society of America 92: 2233-2250.
Ninis, D., Little, T., Van Dissen, R., Smith, E. (2009). “The Wellington Fault – Holocene displacement and slip rate at Emerald Hill, Wellington”. in Barrell, D.J.A., Tullock, A.J. (eds). Programme and abstracts, Geosciences 09 Conference, Oamaru, New Zealand. Geological Society of New Zealand Miscellaneous Publication 128A: 154.
Ninis, D., Little, T., Van Dissen, R., Smith, E. (2010). “The Wellington Fault – Holocene displacement and slip rate at Emerald Hill, Wellington, New Zealand: Progress Report”. Victoria University of Wellington Research Report 28.
Nishenko, S.P., Buland, R. (1987). “A generic recurrence interval distribution for earthquake forecasting”. Bulletin of the Seismological Society of America 77: 1382-1399.
Pondard, N., Barnes, P.M. (2010). “Structure and paleoearthquake records of active submarine faults, Cook Strait, New Zealand: implications for fault interactions, stress loading, and seismic hazard”. Journal of Geophysical Research 115: B12320, doi:10.1029/2010JB 007781.
Rhoades, D.A., Van Dissen, R.J., Dowrick, D.J. (1994). “On the handling of uncertainties in estimating the hazard of rupture on a fault segment”. Journal of Geophysical Research solid earth 99 (B7): 13701-13712.
Rhoades, D.A., Van Dissen, R.J. (2003). “Estimates of the time-varying hazard of rupture of the Alpine Fault, New Zealand, allowing for uncertainties”. New Zealand Journal of Geology and Geophysics 46: 479-488.
Rhoades, D.A., Stirling, M.W., Schweig, E.S., Van Dissen, R.J. (2004). “Time-varying earthquake hazard in the Wellington region”. Institute of Geological & Nuclear Sciences client report 2004/141: 46p.
Robinson, R. (2004). “Potential earthquake triggering in a complex fault network: the northern South Island, New Zealand”. Geophysical Journal International 159: 734-748.
Robinson, R., Benites, R. (1996). “Synthetic seismicity models for the Wellington region: implications for the temporal distribution of large earthquakes”. Journal of Geophysical Research 101: 27,833-27,844.
Robinson, R., Van Dissen, R., Litchfield, N. (2009). “It’s Our Fault – synthetic seismicity of the Wellington region: final report”. GNS Science Consultancy Report 2009/192: 36 p.
Robinson, R., Van Dissen, R., Litchfield, N. (in review) “Using synthetic seismicity to evaluate seismic hazard in the Wellington region, New Zealand”. Submitted to Geophysical Journal International.
Stein, R.S., Barka, A.A., Dieterich, J.H. (1997). “Progressive failures on the North Anatolian Fault since 1939 by earthquake stress triggering”. Geophysical Journal International 128: 594-604.
Van Dissen, R.J., Berryman, K.R., Pettinga, J.R., Hill, N.L. (1992). “Paleoseismicity of the Wellington-Hutt Valley segment of the Wellington Fault, North Island, New Zealand”. New Zealand Journal of Geology and Geophysics 35: 165-176.
Van Dissen, R.J., Berryman, K.R. (1996). “Surface rupture earthquakes over the last c. 1000 years in the Wellington region, New Zealand, and implications for ground shaking hazard”. Journal of Geophysical Research 101 (B3): 5999-6019.
Van Dissen, R., Berryman, K., King, A., Webb, T., Brackley, H., Barnes, P., Beavan, J., Benites, R., Barker, P., Carne, R., Cochran, U., Dellow, G., Fry, B., Hemphill-Haley, M., Francois-Holden, C., Lamarche, G., Langridge, R., Litchfield, N., Little, T., McVerry, G., Ninis, D., Palmer, N., Perrin, N., Pondard, N., Semmens, S., Stephenson, W., Robinson, R., Villamor, P., Wallace, L., Wilson, K. (2009). “It’s Our Fault: better defining the earthquake risk in Wellington - results to date & a look to the future”. in proceedings, New Zealand Society for Earthquake Engineering Technical Conference, Christchurch, New Zealand, 3-5 April, 2009. Paper No. 48: 8p.
Van Dissen, R., Barnes, P., Beavan, J., Cousins, J., Dellow, G., Francois-Holden, C., Fry, B., Langridge, R., Litchfield, N., Little, T., McVerry, G., Ninis, D., Rhoades, D., Robinson, R., Saunders, W., Villamor, P., Wilson, K., Barker, P., Berryman, K., Benites, R., Brackley, H., Bradley, B., Carne, R., Cochran, U., Hemphill-Haley, M., King, A., Lamarche, G., Palmer, N., Perrin, N., Pondard, N., Rattenbury, M., Read, S., Semmens, S., Smith, E., Stephenson, W., Wallace, L., Webb, T., Zhao, J. (2010). “It’s Our Fault: better defining earthquake risk in Wellington”. in proceedings, 11th IAEG Congress, Auckland, New Zealand, 5-10 September, 2010: 737-746.
Wang, N., Rieser, U., Grapes, R. (2005). “Optical luminescence dating of Late Quaternary movement on the Wellington Fault, Upper Hutt area, New Zealand”. Luminescence and Electron Spin Resonance Dating, 2005 Conference, 25-29 July 2005, Cologne, Germany.
Copyright (c) 2011 D.A. Rhoades, R.J. Van Dissen, R.M. Langridge, T.A. Little, D. Ninis, E.G.C. Smith, R. Robinson
This work is licensed under a Creative Commons Attribution 4.0 International License.