VIRTUAL FIELD TRIPS FOR UNDERGRADUATE SEDIMENTARY GEOLOGY: TWO BIRDS WITH ONE STONE

The best way for students to learn depositional environments is to describe and interpret rocks in the field. Virtual Field Trips allow a similar learning process but without regional restrictions. As an unexpected benefit, the quality of student’s field notes have significantly improved through weekly practice. Virtual Field Trips are not single photos. Rather, the idea is to specially take a series of 4-10 photos that mimic a field trip stop. The first shot is always a distant photo, basically giving the context. Later photos give progressively more detail. Including hand samples and/or thin sections is very useful as grain size is often hard to see in photos. Weekly ‘field trips’ synchronize with lecture coverage of depositional environments.

The key to the Virtual Field Trips is their presentation as lab exercises. The instructor goes through an example, with instruction on taking field notes. Then the students are given a ‘locality’ to describe and the instructor leaves the room for 20-40 minutes. This allows the students time to examine each photo, compare any hand samples, and produce a set of ‘field notes’. With the instructor gone, the students feel free to discuss each photo and argue over what is there. Larger classes should be divided into small groups. The ‘field notes’ are collected and graded S/U. Specific weaknesses, for example, poor field drawings, can be addressed and improved each week.

When the instructor returns, the class presents their results. They are usually too reserved to volunteer observations, so each student is called on in turn and asked to “describe something”. Possible answers include color, bedding, sedimentary structures, weathering pattern, lithology, etc. Since no one student is asked for very much, even the weaker students participate. Once a complete description is obtained (perhaps with the instructor’s help), it can be compared to possible depositional environments.

Anecdotal evidence suggests the students remember virtual field trips better than lecture presentation of photos. The quality of field notes on the 2-day class field trip is much better. In addition, scores on photo interpretation during the final exam have risen since virtual field trips were introduced.