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Used this activity? Share your experiences and modifications
This lab allows students to analyze earthquake seismicity from the North Anatolian fault using a variety of methods.
I used this in a intermediate level course on Tectonics. It was an useful way to integrate geophysics into a regular geology course. Before the lab begins, I show students images of the earthquake destruction and explain that they are part of a team sent by the USGS to investigate the earthquake. This pretty minimal back-story seemed to engage the students more than simply asking them to complete the exercise. The final product of the lab is a report for the USGS.
Skills and concepts that students must have mastered
For this lab, students will need to plot points on a stereographic projection and figure out how to plot a position (in digital degrees) on a non-Mercator map projection. Because our labs are four hours long, I use some of the lab time to teach about stereographic projection. Students don't realize they need to do any calculations for plotting seismometer stations on the map without some instruction, so I also spend a bit of time at the beginning of class talking about map projections.
How the activity is situated in the course
I used this as the second lab in the term. Most students finish the individual pieces of the lab but don't have time to synthesize the information in a written report during the four hour lab. Although it is possible to omit the USGS-style report as the final piece of the lab, it is easier to see problems in comprehension by using the report.
Content/concepts goals for this activity
The major reason that I developed this lab was for students to have the opportunity to make and interepret an earthquake focal mechanism from scratch. The additional portions of the lab provide regional context and historical data to develop a better understanding of seismicity in Turkey.
Higher order thinking skills goals for this activity
Students analyze historical seismicity data from the North Anatolian fault and make predictions about earthquake magnitudes and locations through time. They also have the opportunity to place the Izmit earthquake and North Anatolian fault in a tectonic context and speculate about whether the focal mechanism makes sense for this plate boundary.
Other skills goals for this activity
Students learn about online databases (IRIS), and write a report for the USGS incorporating all the information (epicenter, magnitude, historical patterns) about the earthquake.
Description of the activity/assignment
This lab allows students to look at variety of data from the North Anatolian fault in Turkey. Specifically, students have the oportunity to:
- interpret seismograms from the Izmit earthquake in 1999 (while accessing some seismograph station information from IRIS)
- make and interpret an earthquake focal mechanism solution based on these seismograms
- locate the earthquake epicenter
- calculate the moment magnitude of the earthquake using published data showing epicenter locations and displacement measurements
- intepret historical data from the North Anatolian fault and tectonic-scale plate motion information to see what patterns occur in the regional seismicity.
Determining whether students have met the goalsMore information about assessment tools and techniques.
Teaching materials and tips
The seismograms were originally created by Steven Boss, University of Arkansas.
The USGS has some nice summary information on the Izmit earthquake here
Excellent images (with high enough resolution to be useful in powerpoint slides) can be found from the National Geophysical Data Center slide set
Air photos of earthquake damage can be found from Bogazici University: [http://www.koeri.boun.edu.tr/sismo/depremler/onemliler/2011_10_23_van_english_version_v28102011.pdf