An Overview of UCERF3 (the latest earthquake forecast model for CA) and the Implications for Operational Earthquake Forecasting
- Date & Time
- Building 3, Rambo Auditorium
- Ben Brooks
Previous fault-based earthquake forecast models have generally assumed segmentation, excluded multi-fault ruptures, and ignored spatiotemporal clustering (aftershocks and otherwise triggered earthquakes), each of which has been brought into question by recent earthquakes. The Working Group on California Earthquake Probabilities has addressed all these issues in their most recent model: the Third Uniform California Earthquake Rupture Forecast (UCERF3), which is the first model to provide self-consistent rupture probabilities over forecasting intervals from less than an hour to more than a century, and the first capable of evaluating the short-term hazards due to multi-event sequences of complex faulting (and earthquake triggering). We find that combining a fault-based forecast with statistical seismology clustering models (e.g., ETAS) requires both characteristic magnitude-frequency distributions on faults (non Gutenberg Richter), as well as the inclusion of elastic rebound, apparently settling the debate on whether either of these attributes is required. Potential usefulness with respect to operational earthquake forecasting (OEF) is presently being explored.