40 Meter (130 ft) Tsunami Wave Smashes Juan Fernandez Island

Hollywood Backstage ^ | February 27, 2010 | Gwen Spinali

[Defiant]

For the benefit of the simple-minded, they ought to change the numbering of the Richter scale. Since each digit is 10 times larger than the one below, a 1 would be a .001, a 2 becomes a .01, a 3 becomes a .100, a 4 is a 1, 5 is a 10, 6 is a 100, 7 is a 1000, 8 is 10000 and 9 is 100,000. That way people can understand the power of the larger quakes.

When we get those 3.5 quakes that occur frequently on the San Andreas, if it is called a .15 quake, people will understand its magnitude better compared to a 1000.

[SC Swamp Fox]

I just looked at Google Earth, Cumberland Bay is on the north side of the island facing away from earthquake. However, I believe that tsunamis are so broad that it will wrap around a small island like this one.

It appears there is a small fishing village on the east side of Alejandro Selkrik island. I doubt that it still exists.

[LoneRangerMassachusetts]

700 plus or minus tourists.

The swept away can only be subtracted.

[Grunthor]

“130 feet?!? If true, that’s a monster, one of the largest, if not he largest, ever recorded. They need to evacuate ALL the beaches in Mexico and Hawaii”

If true, what about the lesft coast?

[freedumb2003]

That is a brilliant idea. I will use it as an analogy for people who don’t live in Earthquake country.

For the purposes of this, I come up with the 8.9 being a 90,000 on the Defiant Scale (with a 4.0 being a 1).

It was the analysis of the waves that resulted in the Richter Scale — it was one of things that pretty much wrote itself and was used as a tool for science. As a communications tool, it is difficult for people to understand, since they tend to think linearly.

[freedumb2003]

I just saw a great graphic (I will try to find it) showing the trajectories and approximate times.

It looks like most of the West Coast will get hit at 90 degrees, so south facing beaches are the biggest concern.

[GVnana]

Celebutard video here: http://abcnews.go.com/GMA/rising-death-toll-tsunami-watch-88-magnitude-quake/story?id=9963716

[LoneRangerMassachusetts]

Based on the definitions in the chart, one micron is 1/1,000,000 of a meter. One meter equalss 10⁶ microns. The chart looks screwy to me. At magnitude 6, the ground movement is one meter. At magnitude 9, the ground movement is 1000 meters? For a magnitude 6 earthquake, the ususal movement is between a fraction of a foot to little more than a foot.

[Defiant]

the Defiant Scale

LOL. I like that.

Your example really brings it home. If an 8 is a 10,000, an 8.9 is 90,000. People think of a 6 as being worth respect, a 7 as scary and potentially dangerous. If they looked at them as 100 and 1000, and then thought about the power of a 90,000 they would understand better.

[NavyCanDo]

Will Hawaii be at High or Low Tide?

[chris37]

I do not believe that it is possible for an earthquake to displace enough water to cause a 130ft wave.

It likely isn’t going to be anymore than 50 ft.

A 130 ft wave must be caused by something else, such as a long, run out landslide that lands in the water.

[Defiant]

By the way, I was wrong on what a 3.5 would translate to. It would be a .5 on the "Defiant Scale", not a .15. The ".5 ion the Richter scale " makes it 5 times stronger than a 3, and so under the Defiant scale that would be .1 x 5, or .5.

Still, brings it in focus when we get those quakes, and compare them to, say, a 6, which is 100 on the Defiant Scale.

[Between the Lines]

I believe that tsunamis are so broad that it will wrap around a small island like this one.

Thanks for the info. I did a little research and found that the leeward side of a small island hit by a tsunami usually has severe flooding, but that flooding does not typically hit with the same force experienced by the facing side of the island. Nor do they experience the effect of the water being sucked out to sea before the flood (no warning).

I lean something new every day here at FR.

[PSYCHO-FREEP]

You are wrong about that fact. In 1946, a 7.8 Quake centered in the Pacific, hit Unimak Island in Alaska. It wiped a Coast Guard station off the face of the Earth (sitting on a cliff 250’ above the Ocean) with an estimated wave height of around 270 feet. It also deposited a US Submarine moored in the bay, 5 miles inland on a slope 450 feet above sea level.

I know, because I have been there and seen the plaque describing the event as well as the memorial for the dead Coast Guard men. I flew over the Sub sitting on the Mountain side and it is truly amazing the power this wave generated.

[stormer]

Wave height is a function of energy released and the geometry of the area the wave passes over. The largest tsunami wave was in Lityu Bay, Alaska and was, get this, 1720 feet.

[PSYCHO-FREEP]

The town of Kodiak was also nearly wiped off the map by the very phenomenon you are minimizing. The quake occurred 250 miles to the east of Kodiak, and had Afognak Island directly between Kodiak and the Quake.

The largest damage from a Tsunami is not the initial push of flood water or waves, it does most of it's damage as the water suddenly reverses and rushes back out to sea at a phenomenal rate. And the tide does run out beyond sight even on leeward sides of islands hit by Tsunami's. This is well documented from the Alaska Quake of 1964. Cordova was also not spared and it is even more “protected” than Kodiak.

[DollyCali]

Thanks for your information..

I always appreciate the varied backgrounds of FReepers & their areas of expertise & interest.

Need a recipe? Physic’s answer? Psychic answer? FactCheck on BO, NP or HR? Candidate latest? UFO update? Religous brawl? Sweet stuff & graphics (Amys)..

well for all..FR does come through

[chris37]

Yes, but what was that wave caused by?

It was not caused by an underwater earthquake.

It was caused by a high speed land slide falling into the water from above.

[chris37]

In order for an earthquake to cause a 270 ft tsunami, then it must have moved the ocean floor 270 ft, which isn’t very likely. I expect that the wave was caused by an underwater landslide, and not due to ocean floor displacement.

[stormer]

Source of the energy doesn't really matter. In a subduction zone EQ the area of zone of active subduction can stretch for miles. Even a relatively small vertical offset can displace tremendous volumes of water. The energy released will be attenuated with distance, but if the wave enters a confined area or encounters a gradient where the wave can grow without breaking, they can be huge.