Journey to the Center of the Earth

Seismic Waves is an application which allows you to visualize the propagation of an earthquake's seismic waves as they radiate across the Earth's surface and bounce around inside its interior. The app allows you to watch animated simulations of the earthquake waves of ten historical earthquakes that occurred around the world.

As each animated earthquake simulation plays out you can watch the earthquake waves radiate out on a WebGL half-globe. The waves traveling through the Earth's core bounce off and travel through the Earth's Outer & Inner Core. The half-globe is interactive. Therefore, if you want to study the seismic waves traveling through the Earth more closely, you can rotate the globe to get a better view of the Earth's Mantle, Outer Core and Inner Core.

This Seismic Wave simulator provides a great demonstration of how earthquakes can be used to investigate the Earth’s interior structure. It shows both P-waves (pressure; these waves pass through liquid and solid) and S-waves (shear or secondary; these waves only travel through solid - not through liquid). Waves are refracted (change direction) when they travel through different densities. Therefore by measuring the time P-waves and S-waves take to travel through the Earth it is possible to infer the make-up of the Earth's interior.

Seismic Waves was created by Incorporated Research Institutions for Seismology. If you want to know more about seismic waves the IRIS has created many more lessons, animations and posters on seismic waves.