How this map works
The data is the live public feed from the United States Geological Survey, the same source professional seismologists use. Each circle is one earthquake. Bigger and warmer circles are stronger quakes. Because earthquakes are reported continuously from a global network of sensors, the map fills in within minutes of an event anywhere on Earth.
Is the Earth shaking more than usual?
The banner at the top compares the count of magnitude 5 and larger quakes in the last seven days against the long-run USGS average. Seismic activity is naturally bursty, so a quiet week and a loud week are both normal. The index simply tells you where this moment sits against the baseline, without the alarm the headlines usually add.
What the magnitudes mean
Magnitude is a measure of the energy released, and each whole step up is roughly thirty times more energy. Quakes below about magnitude 3 are rarely felt. Magnitude 5 can crack plaster and rattle a region. Magnitude 7 and above are the ones that make the news and reshape coastlines. The filter lets you strip the map down to only the events that matter to you.