Cautionary Note

We understand why you might be interested in obtaining these catalog files, but are concerned that they might be misused. We have merged catalogs from several different sources, and used fairly subjective criteria to rank our preferences. We have used simple, automated schemes to compute magnitudes and remove aftershocks. To the extent that the original catalogs are not valid research tools, neither are ours! Please read the accompanying documentation, and ask whether these catalogs suit your purpose.

Each file is white-space delimiter ASCII data organized into the following columns:

  1. Magnitude (mb for CEUS, Mw for WUS)
  2. Longitude (decimal degrees, east)
  3. Latitude (decimal degrees, north)
  4. Depth (km)
  5. Year
  6. Month
  7. Day
  8. Hour
  9. Minute
  10. Second
  11. Name of source catalog


Although these data have been used by the U.S. Geological Survey, no warranty, expressed or implied is made by the USGS as to the accuracy of the data and related material nor shall the fact of distribution constitute any such warranty, and no responsibility is assumed by the USGS in connection therewith.