What are the factors that determine the time that elapses between an earthquake and it's discovery by seismometers, and how do these factors influence the travel time?What factors influence the time taken for seismic waves to travel to a seismometer?The above poster is correct, but there are also other factors.
Primary waves can be thought of as compression waves (like sound waves) and can travel through all the phases of the Earth (the mantle, crust etc). Secondary waves are shear waves, and hence can only travel through solid material. Liquids cannot support shear, so there is no way of secondary waves to travel through such media.
The above two waves are called body waves, since they travel through the body of the Earth. Of the body waves, secondary waves are the fastest.
The speed of the waves do not remain constant as they change depending on the material through which they propagate. This is the reason you see body waves gradually move away from the line they are travelling in as they travel deeper and deeper. Hence the geology of the area will play a significant role in wave travel times.
There are also two surface waves: Rayleigh and Love waves.What factors influence the time taken for seismic waves to travel to a seismometer?One thing would be weather they are primary or secondary waves, because (if my physics is right) primary waves can travel through anything, solid or liquid, whereas secondary can't. So if a wave is blocked by the Earths magma centre, then it takes longer to get to the seismometer.
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