How swarms differ from aftershocks
In a classic mainshock–aftershock sequence, one large event stands out and smaller events follow. In a swarm, magnitudes are more similar and there is no obvious kingpin event. Both patterns are common on the USGS map — especially in volcanic or geothermal regions and some transform / spreading environments.
What scientists watch
- Location clustering (same fault volume or volcanic edifice)
- Rate of events over time (rising, steady, fading)
- Depth changes and waveform similarity
- Whether a larger event eventually emerges (only knowable after the fact)
What Ring of Fire shows
Our free live map plots observed USGS events. Filters (magnitude, RoF corridor) help you explore density — they do not upgrade a swarm into a forecast. For volcano-related unrest, consult official volcano observatories; our volcano page is a Holocene location catalog, not a real-time alert board.
Further reading
USGS Earthquake Glossary and volcano observatory pages are authoritative starting points. Always prefer official sources for safety decisions.