what is shear wave splitting?
930795
Shear Wave: A wave in which the disturbance is an elastic deformation perpendicular to the direction of motion of the wave. (Shear waves are also called 'transverse waves.')\n\nShear-wave splitting due to the alignment of vertical cracks in the crust has been widely observed in a variety of tectonic settings and data gathering experiments, from earthquake recordings to controlled-source seismic data. It has also been recognized that the polarization of the fast split shear wave is usually parallel to the local strike of cracks (or direction of the maximum horizontal stress), and that the time delay between fast and slow shear waves is closely related to the intensity of crack-induced anisotropy in the medium.\n\nif you wanna see an image of ahear wave aplit then click on the link below.\nhttp://www.missouri.edu/~sandvole/split.html
418175
it will shear at 45 deg, which is, as previously mentioned, the direction of greatest shear stress.  This occurs despite the random structure because it is caused by stress, not structure.  A similar behavior occurs in metals pulled in slow tension, with "shear lips" forming 45 deg from the direction of the tension.
809778
When sound (or other waveform of similar shape, like an AC signal) travels through a medium, its intensity diminishes with distance. In idealized materials, signal amplitude is only reduced by the spreading of the wave. Natural materials, however, all produce an effect which further weakens the sound. This further weakening results from scattering and absorption. Scattering is the reflection of the sound in directions other than its original direction of propagation.  Absorption is the conversion of the sound energy to other forms of energy.  The combined effect of scattering and absorption is called attenuation.  Ultrasonic attenuation is the decay rate of the wave as it propagates through material.\n\nAttenuation of sound within a material itself is often not of intrinsic interest. However, natural properties and loading conditions can be related to attenuation. Attenuation often serves as a measurement tool that leads to the formation of theories to explain physical or chemical phenomenon that decreases the ultrasonic intensity. \n\nThe amplitude change of a decaying plane wave can be expressed as:\n\n A = A0*e^(-kz)\n\nIn this expression "A0" is the amplitude of the propagating wave at some location. The amplitude "A" is the reduced amplitude after the wave has traveled a distance "z" from that initial location. The quantity "k" is the attenuation coefficient of the wave traveling in the z-direction. The dimensions of are nepers/length, where a neper is a dimensionless quantity. The term "e" is Napier's constant which is equal to approximately 2.71828. \n\nAttenuation is generally proportional to the square of frequency. Quoted values of attenuation are often given for a single frequency, or an attenuation value averaged over many frequencies may be given. Also, the actual value of the attenuation coefficient for a given material is highly dependent on the way in which the material was manufactured. Thus, quoted values of attenuation only give a rough indication of the attenuation and should not be automatically trusted. Generally, a reliable value of attenuation can only be obtained by determining the attenuation experimentally for the particular material being used.\n\nThis is why higher-frequency signals tend to produce what is called "skin effect" ... basically, the energy isn't there for the wave to penetrate to any significant depth.
576347
3 dim seismic vibrations
570143
divergent margins = depressurization melting\nconvergent margins = subduction-related partial melting of the overlying mantle wedge through the loss of volatils form the downgoing slab
460913
structures are subjected to 2 types of movement in an earthquake, P-wave and S-wave. P-wave is the sharp up and down movement, called the primary wave. S-wave is the longer lasting side to side movement, called secondary waves. then there are the after shocks. PBS NOVA has several well made documentaries about that stuff.
837968
Well, seismologists have preached the dangers of lateral/shear waves, whch cause the most damage.  This has altered building practices with things like lateral joints.  They also help identify the areas that are most likely to have the strongest shaking (based on soil type and proximity to faults), which helps code get written.
391077
Primary, compression or P-wave and Secondary, shear or S-wave seismic waves have been created at the same point by a seismic disturbance. \n\nThe P-wave reaches the observer first and the S-wave which is slower then arrives.\n\nRock has different densities and hence the velocity of a seismic wave would vary but to a certain degree since both waves have passed through the same rock then the difference between the S and P waves can be used for calculations.\n\nTo calculate how far away the P and S waves were created multiply the time in seconds between the P and S waves by 8 kilometres per second.\n\nTherefore 8*(3*60)= 1440 kilometres or 894.8 miles.
500218
The correct answer is C.  This is referred to as the rheological division of the mantle, as opposed to the chemical division (which puts the mantle into reservoirs such as MORB, HIMU, etc.)  The lithosphere behaves rigidly wheras the asthenosphere behaves plastically.
45616
Fractured crust is the collective term for tectonic plates.
1059131
In the sense of an earthquake, yeah.  That's what it is.  A wave of earth moving out from the central point of origin.  That has nothing to do with the wave-particle duality.  In fact, it's best not to think of it as an actual wave or an actual particle (like a billiard ball).
233546
Anisotropic \n \nPertaining to a material whose electrical or optical properties vary with (a) the direction of propagation of a traveling wave or with (b) different polarizations of a traveling wave. Note 1: Anisotropy is exhibited by non-cubic crystals, which have different refractive indices for lightwaves propagating in different directions or with different polarizations. Note 2: Anisotropy may be induced in certain materials under mechanical strain.
104416
It looks like diffusion. \nSound waves are reflected between parallel lines so that the mulitple reflections makes sound waves diffuse from one point to other. This is the best logical explaination i can think of. But additional info on this question can help to explain further.
747931
The simplest cheapest way to split a laser is with a plate of glass. Shine a laser through it and some with reflect, and some will transmit. Usually most transmits, but you can control the percentage that reflects by rotating the plate until the angle between the laser and the plate is very small. You can get a 50-50 split that way.
1044728
The foci of earthquakes at transform boundaries tend to be at shallow depths.\n\nSee source.
571847
Two traveling waves which exist in the same medium will interfere with each other. If their amplitudes add, the interference is said to be constructive interference, and destructive interference if they are "out of phase" and subtract. Patterns of destructive and constructive interference may lead to "dead spots" and "live spots" in auditorium acoustics.\n\nInterference of incident and reflected waves is essential to the production of resonant standing waves.\n\nInterference has far reaching consequences in sound because of the production of "beats" between two frequencies which interfere with each other. \n\nDiffraction: the bending of waves around small obstacles and the spreading out of waves beyond small openings.\n\nRefraction is the bending of waves when they enter a medium where their speed is different. Refraction is not so important a phenomena with sound as it is with light where it is responsible for image formation by lenses, the eye, cameras, etc. But bending of sound waves does occur and is an interesting phenomena in sound\n\nWhen a vehicle with a siren passes you, a noticeable drop in the pitch of the sound of the siren will be observed as the vehicle passes. This is an example of the Doppler effect. An approaching source moves closer during period of the sound wave so the effective wavelength is shortened, giving a higher pitch since the velocity of the wave is unchanged. Similarly the pitch of a receding sound source will be lowered.\n\nLight in the form of a plane wave in space is said to be linearly polarized. Light is a transverse electromagnetic wave, but natural light is generally unpolarized, all planes of propagation being equally probable. If light is composed of two plane waves of equal amplitude by differing in phase by 90°, then the light is said to be circularly polarized. If two plane waves of differing amplitude are related in phase by 90°, or if the relative phase is other than 90° then the light is said to be elliptically polarized.
377429
It is a divergent plate boundary found running down the middle of the Atlantic Ocean. Hence the name "Mid Atlantic Ridge".\n\nThis is where two lithospheric plates are moving apart from each other.\n\nWhere they spread apart, new continental crust is being created. It is said that the US & the UK move about 1 - 2 inches apart every year. The US is getting further from Europe all the time!