"Seismic Hazard and Risk Analysis" by Robin K. McGuire

Abstract

Probabilistic seismic hazard analysis (PSHA) is the methodology used to estimate how often some chosen level of earthquake ground motion can be reached or exceeded at one or more places of interest. It synthesizes knowledge about where earthquakes occur, how often they occur, and how big they can be; knowledge of the ground motion that is excited by earthquakes and how it changes with earthquake magnitude, distance, and (occasionally) azimuth; and the uncertainties that attend both the models of seismogenesis and the models of ground-motion excitation/propagation (epistemic uncertainty), as well as the intrinsic variability in the way earthquakes actually occur and in the way that ground motion actually happens (aleatory uncertainty). Risk analysis involves the calculation of loss, generally reckoned through damage and loss functions in terms of dollars of replacement costs and/or loss that will be equaled or exceeded per year, given the hazard analysis. Novices to hazard and risk analysis should note that seismic hazard—or any other natural hazard—cannot be reduced; natural hazard analysis is simply a quantitative assessment of what nature serves up in the way of earthquakes, volcanoes, hurricanes, tornadoes, wildfires, droughts, and the like. Risk, however, …