Slow Earthquake Database

User policy (brief summary)

  • Refer designated references for any resultant production.
  • Follow each catalog's individual policy.
  • Use at your own risk.
  • Data may be updated without any notice.
  • Acknowledge our project.
  • Not for commercial use.
  • No redistribution.

* See here for full policy statement

1. Time Span

Start: Duration[day]: End:

2. Catalog

3. Map View

Colored by:

4. Download


Data Format

date: date1 (yyyy-mm-dd)
time: time1 (HH:MM:SS)
year: year1 (yyyy; %04d)
month: month1 (mm; %02d)
day: day1 (dd; %02d)
hour: hour1 (HH; %02d)
min: minute1 (MM; %02d)
sec: second1 (SS.CS; %05.2f)
timezone: time difference from Universal Time [hour] (%f5.1)
lat: latitude [degree] (%9.4f)
lon: longitude [degree] (%10.5f)
dep: depth2 [km] (%8.3f)
mag: magnitude (%f5.2f)
mrr, mrt, mpp, mrt, mrp, mtp: moment tensor (Global CMT) [Nm] (%9.2e)
strike: strike3 [degree] (%6.1f)
dip: dip3 [degree] (%5.1f)
rake: rake3 [degree] (%6.1f)
length: length4 [km] (%4d)
width: width4 [km] (%3d)
slip: slip [m] (%7.3f)
duration: duration5 [s] (%12.2f)
err_t: uncertainty of time [s] (%9.2f)
err_x: uncertainty of latitude [km] (%6.3f)
err_y: uncertainty of longitude [km] (%6.3f)
err_z: uncertainty of depth [km] (%6.3f)
err_lat: uncertainty of latitude [degree] (%7.5f)
err_lon: uncertainty of longitude [degree] (%7.5f)
catalog: name of catalog
ref: reference
udate: date last modified
1 The definition of the reference time may differ between catalogs. It can be origin time or centroid time, for example.
2 The depth may be either estimated by authors or fixed for the analysis (e.g., on the plate interface).
3 The angles are defined as in Aki and Richards (1979, 2002).
4 For a finite fault, length and width are calculated along the strike and dip direction, respectively, from the reference point given by the latitude, longitude, and depth.
5 The definition of duration may differ between catalogs. It can be either estimated by the analysis or fixed for the analysis.


Google Map

Plate boundary: BP2002 [Bird, 2002]


Refer to Policy page for details.

Catalogs originally constructed by authors



Q. Which OS and browser are supported?
A. We develop the website using Chrome and Firefox on Mac. Currently, data download is not supporting for Safari on Mac as well as the feature of showing individual policy by hovering the mouse pointer over catalog buttons.

Q. Why are no data plotted after selecting catalogs?
A. Please confirm the selected catalog’s time coverage. There is also the maximum number of data to be plotted at once, which is ~160,000 events. You might be able to plot more data by selecting catalogs after fixing the time span, instead of changing the period after selecting catalogs.

Q. Why are no data downloaded?
A. Please confirm the selected catalog’s coverage. There is also the maximum number of data to be downloaded at once, which is ~60,000 events with the simplest format and ~10,000 events with full details.

Q. What are "Related phenomena" in Map+DL?
A. We deal with not only slow earthquakes but also earthquakes that are inferred to be related to slow earthquakes including swarm and repeating earthquakes. We decide each catalog's applicability based on scientific reasonability.

Q. Is seismogram available for download?
A. We do not provide waveform data and focus on earthquake catalog data specified by time and location.

Q. How can researchers add own catalogs to the database?
A. We are collecting slow earthquake catalogs to integrate into Slow Earthquake Database. If you are willing to share your published catalogs of slow earthquakes, please participate our project in the following steps.

  1. Check and agree with the general policy of our project.
  2. Send a request through the form including citing information and other requirements. We will guide you how you can send us your catalog.
  3. Send us your catalog in the designated way. We will send you the catalog converted to our unified format together with the finalized version of policy statements.
  4. Confirm the converted catalog and policy. After receiving your confirmation, we will list your catalog on Slow Earthquake Database.