VOLCANO MADNESS: Re: [Geology2] The Big-Shake, Big-Wave Theory (Pacific NW Megaquake illustration)

Thursday, September 1, 2011

Re: [Geology2] The Big-Shake, Big-Wave Theory (Pacific NW Megaquake illustration)

Hi Rog,

Yes. It has happened before and will happen again. Here's one record of what has gone before:

http://en.wikipedia.org/wiki/1700_Cascadia_earthquake

Lin

On Thu, Sep 1, 2011 at 10:26 AM, roger.steinberg <roger.steinberg@btinternet.com> wrote:

First off I would like to say how sorry I am to hear and read about the terrible conditions that the eastern side of the US is undergoing. I hope peace and tranquillity returns PDQ

Does anyone know if the below stuff has actually happened in the past and if so what evidence is there.? I know it is an active zone but how active and how historical?

Rog (UK)

A. MINUTE 0:00. The North American plate slides 57 feet west over the heavier Juan de Fuca plate, which moves east about an inch per year. The quake's initial pressure wave travels through the Earth's crust at 13,000 miles per hour and reaches the Northwest coast in ten seconds.

B. MINUTE 0:00. Displaced water creates a low standing wave, which peels off in two directions. One wave heads toward Japan at 450 miles per hour, reaching Honshu in ten hours. The other will reach the Northwest coast in 20 minutes.

C. MINUTE 3:00. The Northwest coast drops five feet
in elevation.
D. MINUTE 5:00. The earthquake stops. The tsunami is now 35 miles offshore.

E. MINUTE 10:00. The wave is 15 miles offshore. Water at the coast has begun to recede.
F. MINUTE 20:00. The edge of the tsunami hits the coast at flash-flood speed, about 30 mph, and then slows to 11 mph on dry land. The water will rise to 30 feet in places and proceed as far as six miles inland.

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