TRIANGULATION METHOD IN LOCATING EARTHQUAKE'S EPICENTER

Collision of Plate Boundaries

Locating the Earthquake Epicenter

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© DENNIS F. ERASMO

Center of an Earthquake

Triangulation Method

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Objective: Find the Epicenter of an earthquake using Triangulation Method

Materials:

• hypothetical records of earthquake waves
• Philippine map
• drawing compass and ruler

Triangulation Table

Data. Computation is required!

RECORDING STATION	TIME DIFFERENCE	DISTANCE	COMPUTED
Batangas	44.8
Puerto Princesa	32
Davao	38.4

NOTE: Time difference - difference in the arrival time of P-wave and S-wave in seconds.

Things to do in Triangulation

FOLLOW the STEPS ACCORDINGLY

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• STUDY THE DATA

  Shown is the difference between the arrival time of P-waves and S-waves.

• COMPUTE THE DISTANCE

  Distance from the epicenter from each station using formula d=(Td/8sec)x 100km.

• CHOOSE ONE OF THE RECORDING STATION

  Measure the computed distance on the map scale. the scale of the map in Figure 3 is 1.5 cm: 200 km.Set your compass for that computed distance

• AGAIN, ON THE OTHER RECORDING STATION

  Center your compass, then draw a circle.

• REPEAT STEPS 3 & 4 FOR THE REST OF THE STATIONS.

  You should get three circles that intersect or nearly intersect at a point. This intersection is the epicenter.

GUIDE QUESTIONS

Q1. Where is the epicenter of this hypothetical earthquake?

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Q2. What difficulty will you encounter if you only have data from two recording stations?

Difference P & S Waves

GUIDE QUESTIONS

Q3. The distance-time graph above shows that the S-P interval is aout 10 minutes. What is the distance of the epicenter from the seismic station?

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Q4. What do you think is the importance of determining the epicenter of an earthquake?

Determining the location of earthquake epicenters plays a vital role in laying the foundations of plate tectonics.

DepEd LM for Grade 10 Science, 2014

That's how!

Now you know!

Thank you!

"Keep on learning because it leads us to #Success."

@dennszz.