PRACTICAL: Finding the Epicenter

Front

What is the definition of the epicenter in relation to an earthquake?

Back

The epicenter is the point on the Earth's surface directly above the focus of an earthquake, where seismic waves originate.

Front

What are P-waves and how do they differ from S-waves?

Back

P-waves (Primary waves) are compressional waves that travel faster than S-waves (Secondary waves), which are shear waves. P-waves can travel through solids, liquids, and gases, while S-waves can only travel through solids.

Tags

NGSS.HS-PS4-1

Front

How is the difference in arrival times of P-waves and S-waves used to determine the epicenter distance?

Back

The difference in arrival times of P-waves and S-waves is used in conjunction with a travel-time graph to determine the distance from the epicenter, as longer time differences indicate greater distances.

Front

What is the significance of using ESRT page 11 in determining epicenter distances?

Back

ESRT page 11 provides a travel-time graph that allows students to correlate the time difference between P-wave and S-wave arrivals to specific distances from the epicenter.

Front

If the difference between P-wave and S-wave arrival times is 3 minutes 30 seconds, what is the approximate epicenter distance?

Back

The epicenter distance is approximately 2200 km.

Front

What is the formula to calculate the difference in arrival times of P-waves and S-waves?

Back

The difference in arrival times is calculated by subtracting the arrival time of the P-wave from the arrival time of the S-wave.

Tags

NGSS.MS-PS4-2

Front

How do you convert minutes and seconds into just seconds for calculations?

Back

To convert minutes and seconds into seconds, multiply the number of minutes by 60 and then add the seconds. For example, 3 minutes 30 seconds = (3 * 60) + 30 = 210 seconds.

Front

What is the difference in arrival times if P-waves arrive at 3:01:40 and S-waves at 3:05:00?

Back

The difference in arrival times is 3 minutes 20 seconds.

Tags

NGSS.HS-PS4-1

Front

What is the difference in arrival times if P-waves arrive at 1:20 and S-waves at 3:40?

Back

The difference in arrival times is 2 minutes 20 seconds.

Tags

NGSS.HS-PS4-1

Front

What is the maximum distance from the epicenter that can be determined using the P-wave and S-wave arrival time difference?

Back

The maximum distance can vary, but typically it can be determined up to about 10000 km depending on the time difference.