How to locate the epicenter of an earthquake?

Abstract

The location of the focus of origin of earthquakes involves concepts of physics which are interesting and motivating, and do not require very elaborate prior knowledge. The answer to the question “how to locate the epicenter of an earthquake?” is constructed from considerations of mechanical longitudinal waves (waves “p”) and transverse (waves “s”) and the difference in arrival time in a seismological station for of each of these waves. A simulation technique for measuring distances to the epicenter is made with the help of two toy cars moving at different speeds; the need for data from more than just one station to the precise location is discussed. The laboratory exploration of longitudinal and transverse waves in a metal rod is also discussed, with techniques for measuring the speed of longitudinal waves. There is not a “single one” answer to questions such as the one presented here, but many answers with increasing levels of complexity. The decision of what level of response is satisfactory stays with the student, and in general it is the consequence of the size of his/her motivation for the subject.

Keywords

• terremotos
• epicentro
• cinemática
• ondas mecânicas