Earthquake learning center
Understand earthquakes and alerts
Practical, source-backed guides that help you interpret earthquake data, understand sequences and use alert systems responsibly.
Updated August 23, 2026
Read earthquake data with confidence
Learn what the numbers on an earthquake map mean—and why one number cannot describe the shaking experienced everywhere.
Magnitude and shaking
Earthquake magnitude vs intensity
Magnitude measures the earthquake itself. Intensity describes how strongly it shakes at a particular place.
Understand the difference →Reading the map
Shallow vs deep earthquakes
See how scientists classify earthquake depth and why a shallow event may cause stronger surface shaking nearby.
Explore earthquake depth →Sequences, aftershocks and prediction
Put clusters of earthquakes in context without treating normal seismic activity as a deterministic warning.
Earthquake sequences
Foreshocks, mainshocks and aftershocks
Understand the labels scientists use for earthquake sequences and why they can change after a larger event.
Follow the sequence →Prediction explained
Can earthquakes be predicted?
Learn the difference between an exact prediction, a probability forecast and an early warning after rupture begins.
Separate fact from claims →Earthquake alerts and notifications
Choose the right tool by understanding whether it warns about approaching shaking or reports an event after publication.
How alerts work
Notification vs early warning
Why a catalog notification after an earthquake is different from a warning sent before strong shaking arrives.
Compare alert types →Android guide
How to receive earthquake alerts on Android
Compare Android's built-in warning system, USGS notifications and custom-area monitoring.
Set up Android alerts →iPhone and iOS guide
How to receive earthquake alerts on iPhone
Set up official iPhone alerts, understand local early-warning coverage and monitor a custom area.
Set up iPhone alerts →How we research these guides
SeismoWatch explains public earthquake data using primary sources from the USGS and other official agencies. Every guide links its sources, states the limits of earthquake monitoring and distinguishes forecasts or notifications from prediction and emergency warning.
Apply what you learn to live data
Open the latest worldwide earthquake map, see earthquakes reported in the past 24 hours, compare the past seven days, browse recent earthquakes by region, or review recent significant events. Magnitude, depth and event times come from the public USGS catalog and may be revised as additional observations are reviewed.