Frequently Answered Question


Why is a recent earthquake not showing on Seismic Monitor?

An earthquake occured in New Zealand recently, but it is not displayed on the seismic map. Why are some earthquakes missing from Seismic Monitor?


Seismic Monitor is an automated system with thresholds set for the display of earthquakes on a map.

Only earthquakes of magnitude 4.0 or greater are displayed.
See the List of earthquakes in the last 30 days.

Locations and magnitudes are provided to IRIS by the United States Geological Society (USGS).

Events greater than magnitude 4.0 may be missing from the USGS catalog in some parts of the world because local networks have not yet reported them to the USGS. In such cases please check with your local or national network.

Updated: 05/18/2017
23:04:47 v.22510d55