## How do you find P and S wave travel time?

Using the Pwave Swave travel time chart –

## What is the approximate P wave travel time from an earthquake if the P wave arrives?

8 minutes and 20 seconds

## How long does it take an S wave to travel 4000km?

The graph shows that the S-waves need about 12 minutes: 40 seconds to travel the same distance. Therefore, if the time separation between the arrival time of the P- and S-waves is 5 minutes:40 seconds, the epicenter must be 4000 km away.

## How long does it take for a primary wave to travel 2000 kilometers?

about 6.7 minutes

## What difference between P waves and S waves was used to find the earthquake’s epicenter?

The difference in speeds of the P and S waves provide a way to locate the epicenter. The P waves always “wins the race” and the S waves is always the slower “car”. The greater the interval between the arrival of the first P wave and the first S wave, the greater the distance to the earthquake epicenter.

## How do you find P and S waves?

Measure the difference in arrival times between the first shear (s) wave and the first compressional (p) wave, which can be interpreted from the seismogram. Multiply the difference by 8.4 to estimate the distance, in kilometers, from the seismograph station to the epicenter.