Development of the New Zealand community Fault Model – version 1.0

Abstract

There has been a long-identified need in New Zealand for a community-developed, threedimensional (3D) model of active faults that is publicly accessible and available to all practitioners. Over the past year, work has progressed on building and parameterising such a model – the New Zealand Community Fault Model (NZ CFM). The NZ CFM will serve as a unified and foundational resource for many societally important applications such as the National Seismic Hazard Model, Resilience to Natures Challenges Earthquake and Tsunami Programme, physics-based fault systems modelling, earthquake ground-motion simulations, and tsunami hazard evaluation. Version 1.0 of the NZ CFM is nearing completion and release. NZ CFM v1.0 provides a simplified 3D representation of New Zealand’s crustal-scale active faults (including a selection of potentially seismogenic faults) compiled at a nominal scale of 1:500,000 to 1:1,000,000. NZ CFM faults are defined based on surface geology, seismicity, seismic reflection profiles, wells, and geologic cross sections. The model presently incorporates more than 800 triangulated mesh surfaces as representations of active and/or potentially seismogenic faults linked to parameters such as dip and dip direction, seismogenic rupture depth, sense of movement, slip direction, and net slip rate.