CIG Webinar: The Release of the GEM Global Active Faults Database and Global Seismic Hazard Map

Richard Styron

Yesterday (14 November 2019), I gave a webinar for the Computational Infrastructure for Geodynamics (CIG) group, based out of UC Davis. The webinar went well for most of the time, until my internet went out when I had a few slides left. Oh well...

At some point in the future, a youtube video of the webinar will be posted, and I'll link it here so you can hear me say 'Um' a lot while we both simultaneously read my slides.

Unlike the title and abstract suggest, the last half to third of the talk centered around topics of mutual interest to the geodynamics/tectonics/modeling communities and the seismic hazard community. Basically, a lot of the components of PSHA are based on scientific concepts that are not 100% resolved; nonetheless, in order to make a PSHA model, you have to pick something and go with it. However, continued research into these topics could increase the accuracy and reduce the uncertainty or bias in PSHA models, which underpin building codes, insurance rates, and other governmental and economic policies that have actual human impact. If you're a researcher and interested in exploring the societal implications of these topics, please give me a shout.


In late 2018, the Global Earthquake Model Foundation (GEM) released the initial version of several major products relating to seismic hazard and risk, including the Global Seismic Hazard Map, the Global Seismic Risk Map, and the Global Active Faults Database. Though these are intended primarily to support GEM's mission to reduce earthquake risk, they may be of use or interest to geodynamics researchers and the broader Earth science community. The GEM Global Active Faults Database ( is a dynamic, evolving compilation of active faults worldwide, currently containing ~14,000 fault traces. Associated metadata describe the geometry, kinematics, slip rates and other parameters relevant to seismic hazard analysis. Metadata completeness varies regionally, with ~75% of faults having some slip rate information. The GEM Global Seismic Hazard Map ( displays the geographic distribution of Peak Ground Acceleration with a 10% probability of exceedance in 50 years, and is derived from a mosaic of national or regional seismic hazard models created by a variety of organizations including the GEM Secretariat. Additional topics of collaboration or mutual beneficial research between the geodynamics and seismic hazard communities will be discussed.