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Seismograph records and registers powerful earthquakes, Philippines, Dec 2009
Seismograph records and registers powerful earthquakes, Philippines, Dec 2009
Incorporated Research Institutions for Seismology
Iris: Seismograms of Common Events: Compiled
A collection of seismic events recorded near Mount Saint Helens. The seismographs located at stations record seismograms like what are shown here. [2:10]
Incorporated Research Institutions for Seismology
Iris: Magnitude Explained: Moment Magnitude vs. Richter Scale
Scientists have developed far-more sensitive seismometers that, with faster computers, have enabled them to record & interpret a broader spectrum of seismic signals than was possible in the 1930's, when the Richter magnitude was...
Incorporated Research Institutions for Seismology
Iris: Travel Time Curves Described
Learn how we can calculate the distance to an epicenter of an earthquake. [1:19]
Incorporated Research Institutions for Seismology
Iris: Magnitude: Changing an Earthquake's Magnitude (Downgrade/upgrade)
In this animation take a look at two magnitude scales, and use two examples of magnitude changing. [6:54]