Earthquakes
Earth's Continental Plates - Notes for crustal plates and plate tectonics
Types of Earthquake Waves - How does the earth move?
Earthquake Scales - How is the strength of an earthquake measured?
Seismograph - How do I read a seismogram?
Earthquake Info - More useful information.
USGS - Earthquake Website
Seismic Monitor - See where earthquakes are happening today
Seismic Wave Simulator - see how P-Waves, S-Waves, and Surface waves travel through the earth and on the earth's surface