Triangulation Method for Earthquakes

What is the main purpose of using the triangulation method in locating an earthquake's epicenter?

Which formula is used to calculate the distance of the epicenter from a recording station?

What problem arises when trying to locate the epicenter using only two recording stations?

Why is it important to determine the epicenter of an earthquake?

What type of waves are responsible for the vibrations felt during an earthquake?

When preparing to locate an earthquake's epicenter, what materials are essential for the calculation process?

What does the term 'S-P interval' refer to in the context of triangulation?

What happens if the circles drawn from three recording stations do not intersect at a single point?

Triangulation Method

Triangulation is used to pinpoint the epicenter of an earthquake by analyzing seismic data.
The process involves measuring the time difference between the arrival of P-waves and S-waves at multiple recording stations.

Key Concepts

Earthquake: A phenomenon caused by the rapid release of energy, resulting in vibrations of the Earth.
Seismic Waves: Energy waves that travel through the Earth, crucial for locating epicenters.

Procedure for Locating Epicenter

Utilize hypothetical records of earthquake waves alongside a Philippine map, drawing compass, and ruler for the activity.
Calculate the epicenter's distance from stations using the formula:
- ( d = Td \times 100 \text{ km} / 8 \text{ sec} )
  - where ( d ) is distance and ( Td ) is the time difference.
The formula accounts for the 8-second interval between P-wave and S-wave arrivals at 100 km.

Steps to Find the Epicenter

Measure the computed distance on the map using the scale of 1 cm: 100 km.
Set the compass to this distance and center it on one of the recording stations.
Repeat for other stations to draw circles which will intersect at the epicenter.

Questions and Insights

Epicenter Location: Identified at the intersection of the three circles drawn from different stations.
Challenge with Two Stations: Using only two stations leads to two potential intersection points, complicating location accuracy.
Importance of Epicenter Determination: Identifying the epicenter helps in understanding which fault lines are active and predict potential major earthquakes from less active fault lines that store energy.

Triangulation Summary

Triangulation necessitates determining the S-P interval on seismograms for accurate epicenter location.

This quiz explores the triangulation method used to find the epicenter of earthquakes by analyzing seismic data. Learn about the crucial concepts of seismic waves and the calculations required to determine distances using hypothetical records. Test your understanding of the process and formula involved in pinpointing earthquake locations.