Liquefaction exposure across New Zealand State Highways

Content

This dataset (geopackage) indicates liquefaction exposure for State Highway links (road segments between two intersections with either another State Highway or a local road) in New Zealand.

Exposure is based on a binary outcome:

1 = Liquefaction manifestation predicted

0 = No liquefaction manifestation predicted

The dataset includes:

Liquefaction exposure estimates for six return periods: 50, 101, 252, 475, 975, and 2475 years

Liquefaction exposure estimates for 388 individual earthquake scenarios

Coordinate system:

Projection: WGS 1984

EPSG Code: 4326

Data sources

Liquefaction probabilities were calculated using a modified version (Lin et al. 2021) of the geospatial liquefaction model developed by Zhu et al. (2017). This model uses logistic regression to estimate liquefaction probability based on geospatial variables, including:

Peak ground velocity (PGV) in cm/s

Shear wave velocity in the upper 30 m (Vs30) in m/s

Annual precipitation (PRECIP) in mm

Distance to the closest water body (DW) in km

Water table depth (WTD) in meters below ground level (m.b.g.l.)

The model was modified for New Zealand by Lin et al. (2021) to incorporate region-specific datasets for Vs30, DW, and WTD. Evaluations against the 2010–2011 Canterbury Earthquake Sequence and the 2016 Kaikōura earthquake indicated improved prediction performance.

Ground shaking data was obtained from two sources:

2022 National Seismic Hazard Model (NSHM) (Gerstenberger et al., 2022) for return period-based shaking estimates.

Cybershake New Zealand v19.5 (Bradley et al., 2020) for shaking estimates of individual earthquake scenarios.

A State Highway link is classified as experiencing liquefaction manifestation (1) if at least one 100 m-segment along the link has a liquefaction probability ≥ 0.46. Otherwise, the link is classified as 0 (no liquefaction manifestation). 

References

Bradley BA, Tarbali K, Lee RL, Huang J, Motha J, Bae SE, Polak V, Zhu M, Schill C, Patternson J, & Lagrava D (2020). Cybershake NZ v19.5: New Zealand simulation-based probabilistic seismic hazard analysis, Paper 110, in Proceedings, NZSEE 2020 Annual Conference, 22–24 April, 2020, Wellington, New Zealand.

Gerstenberger M, Bora S, Bradley B, DiCaprio C, Van Dissen R, Atkinson G, Chamberlain C, Christopherson A, Clark K, Coffey G, de la Torre C, Ellis S, Fraser J, Graham K, Griffin J, Hamling I, & Hill M (2022) New Zealand National Seismic Hazard Model 2022 Revision: model, hazard and process overview. Report number 2022/57, Lower Hutt, New Zealand: GNS Science. http://dx.doi.org/10.21420/TB83-7X19

Lin A, Wotherspoon L, Bradley B, & Motha J (2021) Evaluation and modification of geospatial liquefaction models using land damage observational data from the 2010–2011 Canterbury Earthquake Sequence. Engineering Geology 287: 106099. https://doi.org/10.1016/j.enggeo.2021.106099

Zhu J, Baise LG, & Thompson EM (2017) An updated geospatial liquefaction model for global application. Bulletin of the Seismological Society of America 107(3): 1365–1385. https://doi.org/10.1785/0120160198