01 / FIELD NOTEBeneath the surface
Explore the moving mantle, seismic waves and fault systems. Twenty topics help connect individual events to the bigger picture.
EARTH & VOLCANO EXPLORERA restless planet.
A restless planet.
A clearer perspective.
Earthquake maps, U.S. volcanoes and the science beneath your feet. One thoughtful place to make sense of a living world.
Free. No ads. No account. The web app is available in your browser.
NATURAL EARTH · ILLUSTRATION20illustrated field notes
6educational model types
12languages in the app
170U.S. atlas entries
FROM A MAP POINT TO PERSPECTIVEMore than where.
More than where.
A sense of what it means.
The USGS past-day catalog stays connected to its original source. Explore what was recorded without confusing observation with prediction.
- Start with the sourceTime, depth, coordinates and the original USGS report put each event in context.
- Find your perspectiveChoose regions manually, compare events, adjust filters and save discoveries.
- Connect the scienceGo from a record on the map to geology, hands-on models and a short quiz.
A FIELD GUIDE TO EARTH01 / FIELD NOTE 
02 / FIELD NOTE
03 / FIELD NOTE
Let curiosity take you further.
01 / FIELD NOTE02 / FIELD NOTEVolcanoes in context
A U.S. atlas with USGS metadata and the latest available notices. Dates and sources help explain what a record actually says.
03 / FIELD NOTEPrepared, at your pace
Read safety information and keep a family checklist in the app without a network connection. Make a plan before you need one.
TRY A SMALL EXPERIMENTOne step.
One step.
A much bigger difference.
Magnitude is logarithmic. Move the slider to compare amplitude ratios and an approximate energy ratio.
Magnitude and intensity, explainedamplitude ratio, ×
approximate energy ratio, ×
An educational comparison: 10^ΔM and ≈10^(1.5ΔM). This does not estimate shaking at a particular location.
FIELD NOTES
Explore the journalA little more understanding.
Magnitude and intensity: why one earthquake feels different from place to place
Magnitude describes the size of an earthquake at its source. Intensity describes its effects at a particular location. Here is how to read both correctly.
Read the story
Epicentre, depth and distance: seeing an earthquake in three dimensions
A map marker tells only part of the story. The focus is underground, the rupture covers an area, and distance from the epicentre alone cannot establish safety.
Read the story
Reading an earthquake map: times, filters and where the data comes from
An earthquake map presents selected source records. Learn what the 24-hour window, revisions, filters and missing events mean before drawing conclusions.
Read the storyFAQ
Good to know before you start.
Does it predict earthquakes?
No. The app displays earthquakes recorded by USGS. It does not predict earthquakes or provide earthquake early warning.
What works offline?
Bundled lessons, safety information and the checklist work without a connection. Downloaded catalog snapshots remain available and are marked stale when a source cannot be reached. New events, original reports and OSM street tiles need a connection.
Does it need location permission?
No. Choose a city or enter coordinates manually. The app does not request GPS access.
Which languages does the app support?
English, Russian, Ukrainian, Spanish, German, French, Portuguese, Italian, Turkish, Indonesian, Japanese and Arabic. The interface, lessons and safety materials are translated.
Does it send alerts or tsunami bulletins?
Background push delivery is not connected in the current Android version. The in-app tsunami bulletin feed requires a configured server. Use official warning services and tsunami centers for warnings.
Your next discovery is already on the map.
Explore the app in your browser.