Origiation of Earthquakes

How Do We Know Where an Earthquake Originated?
Teacher's Guide
Standard Addressed: Grades 6-8: Scientific Inquiry Mathematical Inquiry Technology and Science Processes that shape the Earth Scientific Inquiry Technology and Science Processes that shape the earth Symbolic Relationships Common themes: Models 1 B/1, 2 2 C/2 3 A/2 4 C/ 1, 2 1 B/2 3 A/3 4 C/5 9 B/3 11 B/3

Grades 9-12:

Objectives: By the end of this activity, the student will be able to: 1. Identify P and S waves on seismograms, 2. Determine the distance of an epicenter from a seismic station using travel time curves, 3. Locate the epicenter of an earthquake by triangulation, and 4. Calculate the time of origin of an earthquake based on seismic data Materials Needed: • 3 component seismograms, • • • • Travel time curve, Globe or map for locating epicenter, String (with globe) or compass (with map) Map with Tectonic Plates illustrated.

Jeffrey Barker, Binghamton University Questions or comments: barker@geol.binghamton.edu

Time Management: Teacher Background: A tremendous number of earthquakes occur every year around the world. The vast majority of these earthquakes are too small to be felt by humans. The larger ones, having a magnitude greater than 5, can effect human property and life if they originate near a populated area. However, populated areas do not make up a very large portion of the earth's surface. For this reason, most of the earthquakes that occur each year are not felt either because they are too small, or they are in an area where no one is around to make a direct observation of their movement. To understand Plate Tectonic processes on the Earth, and to better understand where future earthquakes are likely to occur, it is important to know how to locate earthquakes as they occur. The primary tool seismologists use to locate an earthquake's point of origin is a network of seismometers. Seismometers are designed to be sensitive enough to feel even the smallest motion of the...