How do you do you locate earthquake epicenter?

Answer 1

You need to find the difference between the arrival times of P and S waves. From there three or more stations put their results and data together and make circles of distance with a chart. When all three of them cross at a point, that is roughly where the epicenter is.

A more detailed explanation is included below:

To locate an earthquake, you need the data from at least three seismometer stations.

The process is known as triangulation and is described in more detail below.

The seismometer records the P and S-wave arrival times. P-waves travel faster through the earth than S-waves and so they arrive at the seismometer station before the S-waves and are recorded by the seismometer first.

The difference in arrival time between the two types of seismic wave can be used to calculate the distance of the earthquake's epicentre from the seismometer.

DE = DeltaT x (VP - VS) / (VS x VP)

Where:

DE = Distance to epicentre (km)

DeltaT = Difference between P and S-wave arrival time (s)

VP = P-wave velocity (km/s)

VS = S-wave velocity (km/s)

This can then be plotted on a map, by drawing a circle with a radius equal to the distance to the epicenter around the seismometer station. This is then repeated for the other two seismometer stations and the point where the three circles intersect is the location of the earthquake's epicenter.

The above procedure is commonly automated using computers and numerical techniques so that a large number of differing seismic episodes can be processed efficiently.

It should be noted that this is an imperfect process as a number of assumptions must be made about the material through which the seismic waves travel in order to estimate their speed.

Answer 2

To briefly explain the step to the location of the epicenter you must first find the difference betwwen the velocities of p wave and swave. By comparing the differeance you will find which on willl come first and the arrival times of each. The greater the interval of each wave the longer the distance of the epicenter.

Answer 3

You locate it above the focus. The focus is the point where the earthquake comes from. The epicentre is the point on the surface where the most damage is caused, directly above the focus.

Answer 4

Directly above the focus.

Answer 5

You locate it above the focus.

Answer 6

By triangulation