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LESSON 5 · When the Earth Shakes

What We Can Do Instead

Since prediction remains elusive, seismologists focus on probabilistic forecasting — calculating the likelihood of an earthquake of a given magnitude occurring in a region over a time period. The USGS estimates a 72% probability of at least one magnitude 6.7+ earthquake in the San Francisco Bay Area before 2043.

Seismic hazard maps show which areas face the greatest risk based on geological history, fault locations, and soil conditions. These maps inform building codes, insurance rates, and urban planning. They cannot tell you when the next earthquake will strike, but they tell you where to build stronger and where not to build at all.