Modelling hazard from faults with the OQ Engine: new fault sources, epistemic uncertainties and clustering

On May 9th, at the Fault2SHA Learning Series: Modelling Earthquake Clustering. (watch the recording here), Marco Pagani presented recent improvements to the OpenQuake Engine that enhance its capability to compute seismic hazard using fault sources.

Under the category of parametric sources, Marco presented the OpenQuake engine’s 1) new fault typologies: the kite fault source and multi-fault source recently added to the engine to better support models describing ruptures occurring on an unsegmented fault system, as in the case of the UCERF3 model for California; and 2) and a set of new epistemic uncertainties for a segmented fault source where Marco briefly introduced and described aleatory variability and epistemic uncertainty.

In the last part of his presentation, Marco discussed the various options to define non-parametric fault sources in the OpenQuake engine, such as the possibility to define a list of probabilistic earthquake ruptures. He then proceeded to demonstrate some examples of using non-parametric sources to compute seismic hazard at a particular site using the OpenQuake engine.

About GEM’s OpenQuake Engine

The OpenQuake (OQ) Engine, first developed in 2010 is the open-source seismic hazard and risk calculation engine developed by the GEM Foundation in collaboration with a global community of hazard and risk modellers (see https://www.globalquakemodel.org/openquake).

About Fault2SHA Learning Series

The online Learning Series started in January 2021 and is held every second Monday of each month. The purpose of this series is to facilitate collaborations across different disciplines by organising sessions on topics relating to utilising fault data in seismic hazard assessments or hands-on exercises on relevant open-access tools.