- sudden release of energy in Earth’s lithosphere producing seismic waves
- caused by movement along faults at plate tectonics boundaries
- measured by magnitude (Richter/moment magnitude scale) and intensity (Modified Mercalli)
- P-waves (compressional) and S-waves (shear) propagate through Earth’s interior
- surface waves (Love, Rayleigh) cause the most structural damage
- seismology reveals Earth’s internal structure: crust, mantle, outer core, inner core
- major fault zones: San Andreas, Alpine-Himalayan belt, Ring of Fire
- tsunamis generated by submarine earthquakes propagate across entire ocean basins
- secondary hazards: landslides, liquefaction, fires, infrastructure collapse
- earthquake prediction remains unsolved; probabilistic forecasting guides engineering
- seismic data informs plate tectonics models and magnetic field studies