can any1 explain how an earthquake epicenter is located.?
how an earthquake epicenter is located. What is the minimum number of seismographs needed to locate an earthquake epicenter or focus? Why is this?
Okay, this will be fun. 
Anyway, you need at least *3* seismographs. Write that number everywhere. THREE THREE THREE. This is because when you have ONE seismograph, it takes the P and S wave arrival time difference and finds all the possible points that fit this criteria. This will form a circle. A circle has infinite points. This means that any one ofthose points ont he circle can be the epicenter. When you add another seismograph, you have two circles. Two circles can, and 99% of the time *will*, overlap at two points. The epicenter can be any of those two points. When you add a third seismograph, you narrow it down to one point, which is the epicenter.
Earthquake Show Part 2