Earthquakes and the waves they generate are the subject of seismology. The discipline studies the generation, propagation, and recording of seismic waves, as well as the structure of Earth’s interior that the waves reveal. It is both a fundamental and an applied science.

Observational seismology locates earthquakes, determines their magnitudes and mechanisms, and assesses seismic hazard. Structural seismology uses natural and artificial sources to image crustal and mantle architecture. Engineering seismology focuses on ground motion and its effects on buildings and infrastructure.

Seismology provided decisive evidence for a liquid outer core and has mapped subducting slabs and mantle plumes. Real-time networks support tsunami warnings and earthquake early-warning systems. The field continues to advance with denser instrumentation, better computational models, and new analytical techniques.

• Scientific study of earthquakes and seismic waves
• Images Earth’s internal structure
• Supports hazard assessment and early warning
• Combines observation and theory