Active region
Why Japan appears often in earthquake data
JMA describes Japan as one of the world's most active seismic and volcanic areas. That helps explain why offshore context, depth, and local JMA information matter on this page.
Regional earthquake guide
Japan Earthquake Map and Recent Reports
A focused Japan map for recent USGS earthquake reports, with plain notes on offshore reports, depth, and when JMA context matters.
Japan context
Japan earthquake background
This page starts with recent reports. These local notes help the map make more sense.
Local reporting
Magnitude is not the whole story
Japan also uses seismic intensity information to describe observed shaking at a location. That is different from source-reported magnitude.
Source habit
Compare the basic details
For any Japan-area report, compare magnitude, depth, time, and source status before assuming what the event meant locally.
Map reading
How to read the Japan map
Check the reported location, depth, time, and source page before assuming what an event meant nearby.
Offshore context
Start with distance and depth
Many Japan-area reports are offshore. The place name, map point, depth, and source page help explain what the report is describing.
Depth check
Depth changes the reading
A deeper report and a shallow coastal report can mean different things. Depth is context, not a standalone impact measure.
Source link
Check JMA for local detail
For Japan-specific information, JMA reports local earthquake details such as hypocenter, magnitude, and observed seismic intensity.
Source context
How this page uses data
Japan reports often need distance, depth, and offshore context. This page shows a USGS public-data view beside reminders that Japan Meteorological Agency information is the local official reference.
The main earthquake tracker has the broader time and magnitude filters. This page keeps the map frame and notes focused on Japan.
How this tracker works / Magnitude and depth guide / Ring of Fire explainer
Regional guides
Related earthquake guides
Open another focused page with a closer map, source links, and local earthquake background.
Earthquake zone
Ring of Fire
A broad Pacific guide to recent USGS reports, plate-boundary patterns, and why closer regional pages matter.
Region
New Zealand
A New Zealand-focused USGS view with offshore context, depth notes, and GeoNet quake-listing links.
Region
California
A California-focused USGS view with fault background, smaller-report context, and source-status notes.