1. Designing a seismic array: A brief in-class activity Erica Emry – Penn State University Summary: Following some initial lecture on the basics of seismic tomography, students are asked to design an array of seismometers to study a feature of their choice – they then have an example that they can think about later, during more detailed lectures on seismic tomography. Goals: Students identify what they do not yet understand about tomography Students develop their problem-solving and critical-thinking skills, creativity, etc. Instructor identifies possible misconceptions that can be addressed during following lectures.

2. Intended to make students think creatively about tomography by designing their own array Intended to be brief, engaging, and at an introductory level. Structured in four parts: – Identify a feature of interest and make a “back of the envelope” design of a seismic array that will be used to resolve the feature (w/basic straight-ray assumptions) – Post-design array swap/review of other students’ seismic arrays – Before returning reviews: After seeing others’ arrays, student thinks about what she/he would do differently – Returning the reviews: a few more reflection questions, what student might do differently

3. Students must be taught some basic concepts of what seismic tomography is: – A general understanding of the different types of seismic tomography and the parts of the earth through which seismic waves travel – The seismic observables that each technique can detect (i.e. seismic velocity/attenuation) and what physical characteristics they are sensitive to (i.e. temperature, melt, composition) – Example: Overview of Seismic Tomography powerpoint (Michael Wysession, Session 1) Students must be given “the rules” of the chosen region: – Tectonic setting (some suggestions for features of interest?) – Local earthquake distribution – Global earthquake distribution relative to the region Pre-activity Preparation

4. Basic Seismic Tomography Some examples of what might be included in an introductory lecture….. – Images from: http://eqseis.geosc.psu.edu/~cammon/HTML/Classes/IntroQuakes/ Notes/waves_and_interior.html

5. Basic Seismic Tomography Some more examples of what might be included in an introductory lecture….. – (from session 1 Overview of Seismic Tomography)

6. Pre-activity Preparation Maps made using GeoMapApp (http://www.geomapapp.org)

7. Part 1 – design an array: – Identify a feature to study & design an array – Should be quick… 20-30 min? Part 2 – switch designs with peers: – Do you understand what feature is the object of the study – Should the seismic array be able to resolve the intended feature? Part 3 – what would you change, before peer feedback: – Should the seismic array you designed be able to resolve the feature it is intended for? – Can you think of anything you would change about your design? Part 4 – what would you change now: – Similar to Part 3, but following feedback from peers