The New Zealand Community Fault Model - version 1.0: an improved geological foundation for seismic hazard modelling

The New Zealand Community Fault Model (NZ CFM) is a publicly available representation of New Zealand fault zones that have the potential to produce damaging earthquakes. Compiled through collaborative engagement between New Zealand earthquake-science experts, this first edition (version 1.0) of the NZ CFM builds upon previous compilations of earthquake-source active fault models with the addition of new and modified information. Developed primarily to support an update of the New Zealand National Seismic Hazard Model, the NZ CFM comprises two principal components. The first dataset is a two-dimensional map representation of the surface traces of 880 generalised fault zones. Each fault zone is assigned specific geometric and kinematic attributes, including uncertainties, supplemented with a subjective quality ranking focused primarily on the confidence in assigned slip rates. The second component is a three-dimensional representation of the fault zones as triangulated mesh surfaces that are projected down-dip from the two-dimensional mapped traces to a geophysically-defined maximum fault rupture depth. This article summarises the compilation and parameterisation of the NZ CFM, along with background on its relation to predecessor datasets, and forward applications to probabilistic seismic hazard assessment and physics-based earthquake models currently being developed for Aotearoa New Zealand.

Automated summary

The New Zealand Community Fault Model (NZ CFM) is a publicly available model representing fault zones in New Zealand that have the potential to cause damaging earthquakes. It is compiled through collaborative engagement between earthquake-science experts and incorporates new and modified information. The NZ CFM consists of a two-dimensional map representation of fault zones and a three-dimensional representation projected down-dip from the mapped traces. This article summarizes the compilation and parameterization of the NZ CFM, its relation to previous datasets, and its applications in seismic hazard assessment and earthquake modeling for New Zealand.