The speed of P-waves and S-waves can help seismologists to determine what?
409571
The exact location of an earthquake.
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.
579637
Basically it's a complex mathematical process to process the vibration response data obtained from siesmic excitation of an oil field to characterize the field in terms of parameters understandable to the analyst (e.g., porosity and impedance). See the ref.
376274
P waves are called primary waves...they do minor damage...S waves are secondary, they do slightly greater damage...the 'L' waves in an earthquake do the most damage, as they cause a 'rolling' effect radiating from the epicenter of the quake
463260
A GPS unit can track ground swelling (especially around active volcanoes).  It relays information about the position of the ground as it changes.\n\nA reading that changes is a definite indicator of change in the ground and could indicate earthquakes or erupions.\n\nAs for plate tectonics, it relays general continental motion (albeit in inches/year)
724384
There are way too many variables to answer this question appropriately.  i.e. the quake magnitude, the depth of the epicenter, the soil underlying the structure, the rock underlying the structure, the components of the structure - material types (3000 psi concrete vs. 8000 psi concrete, the location and amount of re-bar, the type of footing - spread footings vs piles), if any sort of seismic fitting has been to the structure - addition of dampeners or springs, the list goes on....
643922
No doubt, it's a fact. Besides all evidence already discussed by other answerers (earthquakes, fossil record, continent shapes, geological models), today there are *direct measurements* of the changing distance between tectonic plates, using laser or radio interferometry (see reference).
44625
The speed of sound (at sea level) approximately is 340.29 m/s and can be used as a global estimate for the speed of sound for the purposes of this calculation.  That would mean that students measuring such a sound would need to be seperated by 340 meters to measure even a 1 second delay in sound propagation.  Additionally they would need to be able to perfectly synchronize the start of the sound event and the start of stopwatch event.  Making it even worse is the need to react with enough speed to stop the stopwatch upon reciept of the signal without significant reaction delay.\n\nThe experiment would be simply to accomplish with resources to control synchronization and detection equipment, but it would not be a low-budget, high-school type of experiment.
59451
Plate tectonics is the answer to your questions about weathering and erosion, as well as thickness of the continental crust. Plate tectonics moves and lifts continental plates continuously, and faster than erosion can carry the sediments away. Mt. Everest is a good example of this, as pressure from the adjoining crustal plates is lifting the mountain at a rate of a few centimeters a year. \n\nAs this pressure against the continental plates builds they often fold and break, and this causes parts of the contintal plates to slide up over other parts of the plate, making them thicker that the oceanic plates. \n\nAt present the only way to find the top of the mantle is using seismology. Siesmologists measure the way that shock waves (sound waves) move through the earth when earthquakes happen. By studying the way these sound waves are deflected from different rocks they can tell about how deep the boundary is between the crust and the mantle. \n\nHere is one of the best websites that explains plate tectonics. It has animated illustrations that show moving plates and how they have changed over time:\nhttp://www.ucmp.berkeley.edu/geology/tectonics.html
883081
“Earthquake prediction” in the popular language is consonant with short-term prediction.  Scientists are sure about where earthquakes will occur, and a general time span.  For example, I live in San Francisco, and we know that sometime in the next 30 years, there's going to be a big one.\n\nAt the present time, optimism is rather low about the prospects for short-term prediction, because of its local nature: one would have to be fortunate to have instruments within short range of the future focus of a strong earthquake.\n\nResearch into anomalies in the ratio of P- to S-wave velocities, magnetic fields, resistivity, tilt, emission of noble gases, and so on are no longer at the leading edge of contemporary interest.
598797
seismographs and seismometers
970598
Try this website for information on transverse and longitudinal waves:\n\nhttp://www.kettering.edu/~drussell/Demos/waves/wavemotion.html
669974
Check to following link to know more about Tsunami.\n\nIt's not possible to accurately predict plate tectonics  currently.
410632
the beginning of an earthquake are foreshocks. these foreshocks have P-waves, s-waves and surface waves attached to it.
913325
If we assume SHM, then\n\n(a) for a given amplitude A, the max velocity and max acceleration is greater for higher frequency sounds, because SHM is given by the following equations:\n\ny(t) = Asin(2πft + γ) where γ is a phase factor\nv(t) = dy/dt = 2πfAcos(2πft + γ)\na(t) = dv/dt = -(2πf)²Asin(2πft + γ)\n\n(b) For A = 1.0 x 10^-8 m and f = 20.0 Hz\n\nv(max) = 2πfA = 1.26 x 10^-6 m/s\na(max) = -(2πf)²A = - 1.58 x 10^-4 m/s^2
56561
In seismology, Love waves (also named Q waves) are surface seismic waves that cause horizontal shifting of the earth during an earthquake. A.E.H. Love predicted the existence of Love waves mathematically in 1911: from him they take their name. They form a distinct class, different from other types of seismic waves, such as P-waves and S-waves (both body waves), or Rayleigh waves (another type of surface wave). Love waves travel with a slower velocity than P- or S- waves, but faster than Rayleigh waves.\n\nThe particle motion of a Love wave forms a horizontal circle or ellipse moving in the direction of propagation. Moving deeper into the material, motion decreases to a "node" and then alternately increases and decreases as one examines deeper layers of particles. The amplitude, or maximum particle motion, decreases rapidly as one examines deeper layers of particles.\n\nSince Love waves travel on the Earth's surface, the strength (or amplitude) of the waves decreases exponentially with the depth of the earthquake. However, given their confinement to the surface, their amplitude decays only as\n"1/sqrt(r)"\nwhere r represents the distance the wave has traveled from the earthquake. Surface waves therefore decay more slowly with distance than do body waves, which travel in three dimensions. Large earthquakes may generate Love waves that travel around the Earth several times before dissipating.
416466
Patterns of seismic activity along a fault line.\n\nScientists set up seismographs to measure this activity. Movement along faultlines is not uncommon. But we do not usually feel it b/c it is not strong enough. They, however, can detect these slight movements w/ their sensitive equipment.\n\nThere are some other signs as well. An increase in geologic activity near a faultline can give clues. Uplifting of land is one. Increases in geothermal activity may be another.