OpenQuake Implementation of the Canterbury Seismic Hazard Model

This article describes the release of the GNS Science Canterbury Seismic Hazard Model (CSHM), as implemented in the Global Earthquake Model's OpenQuake software. Time-varying models are implemented for the 50 yr time period between 2014 and 2064, as well as the 1 yr period from 1 September 2018 to 31 August 2019. Previous implementations have been confined to GNS in-house software, and although source model input files have been made publicly available, this implementation improves the levels of visibility, documentation, and version control. Because of practical constraints in preparing a model for routine analysis, some corrections and changes to the previous implementations have been made. These constraints highlight issues for consideration when developing future hazard models, particularly the necessity of maintaining a balance between best-practice science and practical model implementation. By implementing the CSHM in OpenQuake, the model is now in a form that allows users to obtain model outputs for engineering design, risk analyses, and prospective model testing.