Matthew d'Alessio

El Cerrito High School

Introductory geology class for majors or non-majors Designed for a geophysics course

Activity has no prerequisite skills.

I use this as the first activity on the first day of the new semester to motivate

Using some of the fundamental principles of geology (superposition, cross cutting relations, original horizontality, and uniformitarianism), students can reconstruct the sequence of events that shaped a landscape.

* Using detailed observations to reconstruct a sequence of events.
* Understanding how spatial relationships reveal clues about timing.
* Becoming familiar and comfortable with problems with no "right" answer.

The activity begins by asking students to look at a drawing of a crime scene. The crime scene is specifically drawn so that illustrates several key geologic principals, but to the untrained eye it appears as a murder that took place inside an office. After quietly looking at the image for a few minutes alone, they share with a partner what they think happened. As a class, we record a list of "Observations," making sure to use the opportunity to highlight the difference between observation and interpretation. After we complete the list of observations, students then offer their interpretations about the sequence of events. Without using any new vocabulary, the teacher makes sure to highlight the geologic principles of original horizontality, superposition, cross cutting relations, and uniformitarianism in the students' interpretations. After students share enough competing theories, the professor shows slides of geologic examples that have things in common with parts of the crime scene and points out the similar processes. The activity eventually ends without a clear answer about "whodunnit." This open ending leaves students frustrated, but it really gets across the point that we can never know the exact answer to some problems, we can only come up with viable theories. Students continue to ask for months about what "really" happened, but I never tell them :-) Has minimal/no quantitative component Uses geophysics to solve problems in other fields

Show students a photograph of a landscape with folded or faulted layers and ask them to describe the sequence of events that shaped that landscape.

GeoSleuth Murder Mystery