IRIS: LOCATING AN EARTHQUAKE

Locating An Earthquake Using Triangulation

The arrival times of P and S waves from an earthquake are used to determine the location of an earthquake. Each station on the interactive map recorded an earthquake with a characteristic seismogram. Roll over the stations to see the epicenter triangulated. Touch buttons to watch movie of seismic waves, or touch "Walk-run" button to see wave travel can be demonstrated with a class.

https://www.iris.edu/hq/inclass/interactive/locating_an_earthquake_using_triangulation
https://www.iris.edu/hq/files/interactives/HowAreEQLocated_WalkRunActivity.html

VIEW the interactive in a separate tab, by clicking on "Open Resource". (Note some browsers lack the plugins for rollovers.)

OR click Download All.  AFTER downloading, you can Open either:

•  by using Flash player, or
•  by clicking File > Open from within your browser, find the file on your computer, and it should open as an interactive file. 

Keypoints:

Rolling over buttons indicated by pointing fingers reveals:

• Information and seismograms from 3 widely spaced seismic stations
• Use the stations to triangulate an epicenter location
• Watch the earthquake waves progress from epicenter to each station.
• Watch the "Walk-run" classroom activity animated in upper bos.