Can you feel the wave?

An earthquake is caused when energy trapped in the crust is greater than the strength of the weak spots in the crust, called faults, is releases along those faults and travels outwards in seismic waves. Waves are divided into body waves and surface waves. The body waves come first, followed by the surface waves. The body waves consist of the primary compression wave (P-Wave) which pushes and pulls rock and sediment, and the shear wave (S-Wave) which moves like a snake pushing the land up and down. Surface waves consist of Love waves which also move like a snake but sideways as opposed to the vertical movement of the S-Wave, and the Rayleigh Wave which moves the earth vertically like the S-Wave, but in a slower manner more like rolling ocean waves.

Generally you will feel shaking from the body waves first, followed by the shifting of the love wave and then the roll of the Rayleigh wave.

During the Great Sumatran Earthquake of 2004, the coastline of Sumatra actually subsided and some of the coast was submerged by the ocean. This 9.3 earthquake was caused by the same stresses currently at work in the Cascadia Subduction zone.

The 1964 Alaska earthquake,a 9.2 magnitude, cause extensive landslides and generated the expected tsunami. This earthquake is similar to what is expected along the Cascadia subduction zone, in that it is a mega thrust earthquake whose uplift effect on the crust generated liquefaction, landslides and a tsunami.

Can you feel the wave?

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COME TO "ESCAPING GROUND ZERO" OUR WORKSHOP ON HOW TO GET

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