A Software Tool for Hybrid Earthquake Forecasting in New Zealand

Abstract

Earthquake forecasts estimate the likelihood of seismic activity within a specific region over a given timeframe, utilizing historical data and patterns from past earthquakes. In New Zealand, the GeoNet program within GNS Science is the main source of geological hazard information and has publicly provided earthquake forecasts since the Darfield earthquake in September 2010. The generation and provision of initial forecasts and subsequent updates have relied on extensive time commitments of experts. The growing use and the desire to make forecast delivery less dependent on personnel capacity have motivated the development of a robust software solution through a hybrid forecast tool (HFT). The HFT is composed of forecast models that cover several different timescales: short term (ranging from a few hours to several years, based on empirical relations for aftershock decay), medium term (spanning years to decades, utilizing the increased seismic activity preceding major earthquakes), and long term (covering decades to centuries, combining information from the spatial distribution of cataloged earthquake locations and slip rates of mapped faults and strain rates estimated from geodetic data). Originally, these models were developed over many years by individual researchers using various programming languages such as Fortran, Java, and R, operating on separate operating systems, with their features documented and published. The HFT unites these models under one umbrella, utilizing a Docker container to navigate disparate software library compatibility issues. Furthermore, the HFT offers user-friendly navigation through a graphical user interface and a command-line feature, facilitating the configuration of automatic and periodic forecast runs. The stability and integration provided by the HFT greatly improve the capability of GNS Science to provide forecasts that inform responses to significant regional seismic events and bring New Zealand closer to automated and operational earthquake forecasting. Although HFT is specifically designed for New Zealand’s earthquake forecasting, the framework, implementation, and containerization approach could also benefit forecasting efforts in other regions.