One map, every agency
SeismoAtlas collects earthquake reports from seismological agencies around the world, recognises when several of them describe the same earthquake, and shows all of their numbers side by side.
Why several agencies
No single network records every earthquake equally well. The U.S. Geological Survey covers the whole planet and the United States in detail. National agencies such as Japan’s JMA or Italy’s INGV run dense local networks and usually locate their own earthquakes best. Global centres such as GFZ’s GEOFON publish fast solutions for larger events anywhere. Each uses its own stations, Earth models and magnitude types, so their numbers for one earthquake differ slightly.
How events are merged
When a new report arrives we compare it with recent events. If the origin times, epicentres and magnitudes are close enough, it is the same earthquake. The tolerances grow with magnitude: for a magnitude 2 we allow 25 seconds and about 65 km; for a magnitude 7, 90 seconds and 160 km, because agencies disagree more on large, often offshore events. An event never holds two reports from the same source.
The headline numbers come from the solution most likely to be accurate: a regional network inside its own territory first, then reviewed solutions, then global ones. Every other solution stays visible on the event page, for example “USGS M5.1 · GFZ M5.0 · JMA M4.9”. We mark whether the headline solution has been reviewed by a seismologist or is still automatic, and when a magnitude has been revised since it was first published.
What we add
- Place names and distances from the GeoNames gazetteer, in local spelling.
- Plain-language context for each magnitude, and an estimate of shaking at nearby cities from a published intensity prediction equation, labelled as an estimate.
- Anonymous felt reports from visitors, aggregated on a coarse grid.
- Regional statistics, a historical explorer over the USGS catalogue back to 1900, and alerts you can subscribe to.
What we do not do
SeismoAtlas is not an early-warning system and does not issue warnings. Events appear minutes after an agency publishes them. We never invent tsunami information: when relevant we link to the official tsunami warning centres. For safety advice, follow your national agency and local authorities.
Who runs it
SeismoAtlas is built and published by Novpix. Questions and corrections: hello@seismoatlas.com. The data and its licences are described on Data sources; developers can use the public API and MCP server.