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Regions of the Earth: Rigidity, Age and Wave Speed

I am not sure if I did the following 3 questions properly (please see attached file). Can you please check them?

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Please see attached response, which is also presented below. The only change that I made was to switch the order for one of the questions (i.e., lithosphere and asthenosphere) as the lithosphere is more rigid than is the asthenosphere. Otherwise, great job!

1. Correct answer. Good Work!

4. Rayleigh
3. Love
1. P-wave
2. S-Wave
5. Tsunami

P-Wave fastest ~6.0 Km/sec
S-Wave ~3.5 km/sec
Surface (slowest) ~3.2 km/sec (Love then Rayleigh waves)
http://www.ess.washington.edu/~tsclasses/315/Lab%201%20Seismic%20Hazards.pdf

The existence of Rayleigh waves was predicted in 1885 by Lord Rayleigh, for whom they were named. They are distinct from other types of seismic waves, such as P-waves and S-waves, which are both body waves, or Love waves, another type of surface wave. Rayleigh waves are generated by the interaction of P- and S- waves at the surface of the earth. The Rayleigh wave travels with a velocity that is lower than the P-, S-, and Love wave velocities. Emanating outward from the epicenter of an earthquake, Rayleigh waves travel along the surface of the earth at about 10 times the speed of sound in air (http://www.nationmaster.com/encyclopedia/Rayleigh-waves).

Tsunami - Fastest wave except when slowed down by such things as the trench

Once a tsunami has been generated, its energy is distributed throughout the water column, regardless of the ocean's depth. A tsunami is made up of a series of very long waves. The waves will travel outward on the surface of the ocean in all directions away from the source area, much like the ripples caused by throwing a rock into a pond. The wavelength of the tsunami waves and their period will depend on the generating mechanism and the dimensions of the source event. If the tsunami is generated from a large earthquake over a large area, its initial wavelength and period will be greater. If the tsunami is caused by a local landslide, both its initial wavelength and period will be shorter. The period of the tsunami waves may range from 5 to 90 minutes. The wave crests of a tsunami can be a thousand km long, and from a few to a hundred kilometers or more apart as they travel across the ocean. On the open ocean, the wavelength of a tsunami may be as much as two hundred kilometers, many times greater than the ocean ...

Solution Summary

This solution provides and explains the best answer to three multiple-choice questions regarding the rigidity of the regions of the earth, the age of the earth and the speed of different types of waves.

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