Tap a dot for the earthquake, a line for the plate boundary, or empty map for the plate you are on
tectonic-pulse [live|replay|quake|stats|more] place-or-plateFive steps from a first look at the stream to the plate under a single earthquake.
The Live tab lists the earthquakes of the past week, newest first, from USGS and EMSC as one list. A new one flashes on the map with a ring, and for 25 minutes its P and S waves spread out. A sentence on top says whether the day is normal or not.
The size of a dot is the magnitude; the colour is magnitude, depth or age (press C). The coloured lines are the edges of the 52 tectonic plates. Choose the smallest earthquake to show with the buttons, or Q.
Tap a dot. The Quake tab gives the size, depth and energy, the plate it happened on, the kind of boundary nearest to it and the speed of the plates there, and the earthquakes around it a week before and after.
In Replay pick 24 hours, 3, 7 or 30 days and press Space. The earthquakes appear on the map when they happened. Drag the time bar to go back; Back to live (N) returns to the stream.
Near me tells you the plate you are on and the closest recent earthquake. Stats counts the window by hour, magnitude, depth and plate. Save a list as csv or GeoJSON, switch on a sound for new quakes, or Copy link to share one.
The default colour of a dot. Size grows with magnitude too:
Each line is where two plates meet, in the colour of the way they move:
For the first 25 minutes after an earthquake:
The scale is logarithmic. One whole step up means:
The outer shell of the earth is cut into about fifty tectonic plates that creep a few centimetres a year, as fast as a fingernail grows. Where two plates meet they lock, the stress builds for decades or centuries, and an earthquake is the moment the rock slips. That is why the earthquakes on this map are not spread evenly: they draw the edges of the plates, most of all the ring round the Pacific. The page shows both at once, the live earthquakes and the plates under them.
The USGS and EMSC catalogues merged, so an earthquake that both report counts once.
The Bird (2003) plate model with 5,824 boundary steps, each with a kind and a speed.
Rings that spread from every new earthquake for 25 minutes.
Tap an earthquake or a line and read the plate, boundary and plate speed.
Watch 24 hours to 30 days of the earth in under a minute, and step through it.
The feeds are fetched by your browser. Nothing goes through a server of mine.
No single agency sees every earthquake first. The USGS (United States Geological Survey) runs the most used global catalogue; the EMSC (European-Mediterranean Seismological Centre) collects the reports of more than a hundred national networks and is often a few minutes faster for Europe, Asia and Africa. Your browser asks both directly: the USGS summary feeds every 30 seconds for the last hour and every few minutes for the last day, week and month, and the EMSC service every two minutes, plus the EMSC live stream that pushes a new earthquake the moment it is published.
| Window | Smallest earthquake | Source |
|---|---|---|
| Last hour to last 3 hours | every size | USGS and EMSC |
| Last 24 hours | every size the catalogues list (mostly M 1 and up) | USGS |
| Last 7 days | M 2.5 and up | USGS and EMSC |
| Last 30 days | M 4.5 and up | USGS |
Two reports are treated as the same earthquake when they are less than 90 seconds apart, less than 200 km apart and within one magnitude of each other. The page keeps the USGS values when it has them, and marks the source on every line: U for USGS, E for EMSC and U+E for both. If the two catalogues disagree on the magnitude, the earthquake page shows both numbers. The rule can fail in a busy aftershock sequence, where two real earthquakes are close in time and place and can be taken for one, or where the catalogues put the same earthquake further apart than the rule allows and it appears twice for a while.
Magnitude is a number for the size of an earthquake, measured from the waves on seismometers. The scale is logarithmic: one whole step is ten times the movement of the ground and about 32 times the energy. The page estimates the energy as 101.5 M + 4.8 joules and also writes it in tonnes of TNT. This is the energy that goes into the waves, and a rough value: it says nothing about the damage, which depends on depth, distance, the ground and the buildings.
| Magnitude | Per year, worldwide | Class | Energy | Typical effect |
|---|---|---|---|---|
| M 4 | over 10,000 | minor | 15 t TNT | felt near the epicentre, rarely any damage |
| M 5 | about 1,500 | light | 477 t TNT | shakes things indoors, damage is rare |
| M 6 | about 130 | moderate | 15 kt TNT | can damage poorly built buildings near the epicentre |
| M 7 | about 15 | strong | 477 kt TNT | can be destructive over an area of about 150 km |
| M 8 | about 1 | major, great | 15 Mt TNT | serious damage over a large area |
| M 9 | about one in ten years | great | 477 Mt TNT | rare: the energy of a very large fault, 1,000 km long |
The counts are the long-term averages of the USGS statistics, rounded. The depth is where the rock first slips. Shallow earthquakes (under 70 km) are the most common and, for the same magnitude, the most damaging at the surface. Intermediate ones (70 to 300 km) and deep ones (more than 300 km, down to about 700 km) happen only in subduction zones, where a cold plate sinks into the mantle. They shake a wider area but more softly. Under a magnitude of about 4.5 the catalogues are not complete in many parts of the world, so the small earthquakes show where the networks are dense (the US, Japan, Europe) more than where the earth is active.
The lines on the map come from the model PB2002 of Peter Bird (2003), which splits the surface into 52 plates, from the huge Pacific plate to small ones such as Juan de Fuca, along 5,824 boundary steps. Each step has a kind and the speed at which the two plates move against each other, from a global model of plate motions. The page saves the model with itself, so the lines are the same on every visit.
| Boundary | Motion | What you see |
|---|---|---|
| Ridge or rift | pulling apart | shallow, mostly small earthquakes; new sea floor (Mid-Atlantic Ridge, East African Rift) |
| Transform | sliding past each other | shallow, sometimes large (San Andreas, North Anatolian fault) |
| Collision | pushing together | wide belts of shallow earthquakes under mountains (Himalaya, Zagros) |
| Subduction | one plate dives under the other | the biggest earthquakes, shallow to deep, and the tsunamis (Japan, Chile, Sumatra) |
When you open an earthquake the page finds the plate that contains it and the nearest boundary within 300 km, and reports the kind, the distance and the speed. The speeds are a few millimetres to about ten centimetres a year. Take them as typical values, not as the motion on the day: the plates move steadily, and an earthquake is a jump of a few metres, once in a long time. Two limits to keep in mind. A line in the model is a clean curve, while the real boundary is often a belt tens or hundreds of kilometres wide, so a distance of 50 km says "close", not an exact number. And some earthquakes are far from any boundary, inside a plate, on old faults; the page says so when there is no boundary within 300 km.
An earthquake sends two kinds of waves through the rock. The P wave (primary, a push and pull) is the fastest, about 6 to 8 km a second in the crust and faster deeper down. The S wave (secondary, a sideways shake) is slower, about 3.5 to 4.5 km a second, and it carries most of the damage. The delay between the two is how a seismometer, and a person, can tell how far away an earthquake is: each second between the P and the S wave is about 8 km of distance. The page draws a white ring for the P wave and a dashed ring for the S wave, growing from the epicentre at 8 and 4.5 km a second, for the first 25 minutes.
It is a picture, not a forecast. The real waves bend and change speed with depth and with the rock, they come in many more kinds (the surface waves arrive later, and are slower again), and an earthquake that the catalogue publishes several minutes after it happened shows rings that are already large. Use them to see how the waves spread, not to work out when you would feel it.
This is a map of what has happened, not an early-warning system. The catalogues need one to several minutes to publish an earthquake, and the first numbers are automatic: magnitude, depth and position are often revised in the first hours, and a very large earthquake is usually given a higher magnitude a day later. The page can show an earthquake that is later removed or moved. It does not forecast earthquakes; nobody can say when or where the next big one will happen. The count of the last 24 hours against the week is a description of the past, not a sign that something is about to happen.
The data can fail. Each feed is fetched by your browser and can fail on its own. When no catalogue answers, the page says so and shows no calm verdict, since silence from a feed is not a quiet earth. The EMSC live stream can be silent for long stretches and also repeats revisions of old earthquakes, which the page ignores. Details are under More, in Live data. If you feel strong shaking, drop, cover and hold on; near the sea, go to high ground. For anything urgent follow your civil protection and the official service of your country.
The map runs in your browser. Near me asks your browser for your location and uses it only on this page, to find your plate and the closest earthquake; the position is not sent anywhere. The live data comes from USGS and EMSC, and the map tiles from Esri, so those services see your address as for any web page. Your settings (the map, the layers, the smallest magnitude, the time zone, the sound) stay in this browser's local storage under the keys tp-ui and tp-unit; Clear saved data under More removes them. The page uses cookie-free analytics (Simple Analytics) and no advertising.
Tsunamis, volcanoes, the sun and the sea are on the same kind of map. There are more tools in the full list.