NOTE: As of 31st Jan 2021 this page replaces the webicorder page at https://pasadena.wr.usgs.gov/webicorder.
A webicorder is a digital record of the seismic signal from a seismometer. These digital seismograms replaced analog records as originally seismographs recorded their data onto a paper medium called a helicorder. Currently seismogram, helicorder, and webicorder are commonly used interchangeably as they all represent the same data.
Station Map 
This map displays all of the stations in the Southern California Seismic Network (SCSN) that have webicorder files available to view.
Click on a station icon to reveal its Station ID then on the Station ID to navigate to its corresponding entry in the list below.
Use the zoom buttons to view more cities and precise locations.
Webicorder Stations
Click on the station names below for a list of available webicorder files.
For each station there are 14 files representing the past 7 days of seismic data at 12 hours per file. Each line of the webicorder is 15 minutes of time, “read” from left to right then connecting down to the left side of the next line. The lines are colored for visual differentiation and do not indicate anything other than the next 15 minute line. Pacific time (PST/PDT) is displayed on the left side and Coordinated Universal time (UTC) on the right. Minutes are labeled along the bottom.
Webicorder files are uploaded once daily at the end of each day UTC (4pm PST, 5pm PDT) for the preceding 24 hour period and the preceding 7 day period.
The waveforms displayed are broadband (20-40 samples/second), high gain, vertical component channels using the SEED format channel type BHZ. These webicorders are for visual purposes only and cannot be used to locate, identify, or analyze an earthquake with any degree of accuracy. Station selection subject to change as necessary.
For a real-time feed from a selection of SCSN seismic stations visit our Live Seismograms Feed and for up-to-date information on recent Southern California earthquakes visit the Latest Earthquake Information.
