Active Fault Databases for Central America and the Caribbean, and the GEM Global Active Fault DB

Richard Styron

Last week I was fortunate to give a presentation at the GEM Foundations's CCARA Final Workshop in Santo Domingo, Dominican Republic. The CCARA, or Caribbean and Central American Risk Assessment project, is a USAID-funded project to develop a unified seismic hazard, risk, and social vulnerability model for the region. Consistent with GEM's work, this is a source-to-sink model, in which we developed new fault and earthquake catalogs, then made a new seismic hazard model based on this, and piped this in to the risk and vulnerability models (which also use new databases for the built environment and vulnerable populations developed at GEM with our collaborators in the region).

My role in this was to develop an active fault database for the region. I've written about this nearly a year ago, but the database has seen a bit of improvement since then, and a paper presenting it is in review with Geosphere. The talk also briefly mentions the GEM Global Active Faults Database, which is my main project at GEM and is coming together nicely.

The slides for the presentation are here:

These regional projects we've been doing at GEM have been very good for updating regional seismic hazard models, with higher resolution, better data and better modeling strategies. They're also turning into springboards to allow more local governements or other stakeholders, such as the geologic surveys of individual nations, to work with us to build even higher-resolution national models. This allows us all to really focus on data and model resolution, and to work closely with the stakeholders to have the results to guide updating building codes, identifying particularly vulnerable populations and infrastructure, and making a base for city- or site-specific work such as power plants or hospitals.

With seismic hazard and risk, the nature of the game changes somewhat as the resolution changes--the regional tectonics and so forth become less important, the geometry of individual faults becomes more important, as do the particular site conditions (the type of soil, etc.) and the layouts of the cities, neighborhoods and other critical infrastructure. The computational strategies in the modeling can change as well. Changing the scale of the work is challenging and exciting, and I'm looking forward to doing some higher-resolution geology in the future.

Thanks to USAID for funding this important work, and to our colleagues at ONESVIE and elsewhere throughout the region for being great collaborators and hosts!