Students will:

1. Visualize and interpret collected field data (mainly planar orientation data) using all three modules in Visible Geology (Geology Explorer, Apparent Dip, and Stereonet) for tasks such as converting between true and apparent dip and interpreting planar data on a stereonet projection.
2. Create models to help visualize folded bedding and compare their models with collected field data.
3. Begin to develop intuition about what different fold patterns look like, how to choose useful locations for geologic cross-sections/profiles, and what data to include in those cross-sections.

This activity is used as lab activity the week following a 3-day (weekend) field trip where students mapped folded beds and took structural orientation data with Brunton compasses (see attached geologic map of field area). This activity is followed by the completion of a full field trip report including a final geologic map, geologic cross-section, data plots, and structural interpretations. Students in this class are typically juniors or seniors who have already taken an introduction to field methods class. This field trip and activity takes place in the second half of the semester, after we have covered stresses and brittle and ductile deformation. In previous class/lab exercises, they learned about making and reading planar and linear data on Stereonet projections, using Visible Geology to visualize how tilted beds interact with topography (Abbey, 2026: Rule of V's Teaching Activity), making cross-sections, and seeing folds in map patterns. This trip and activity allow students to continue to practice what they previously learned and apply that to a specific area they have seen and observed in-person.

This activity could easily be adapted to follow a trip from any other field area, or even to make models and interpretations from previously published geologic maps.

This activity is run the week after a 3-day field trip to an area where students measure and map a large plunging syncline.
In the lab following the trip, the students:

1. Use a computer and the online Visible Geology web-based application to complete the activities, which include visualizing folds with different wavelengths and amplitudes, and an axis that plunges. They try to create a model for what they think they saw in the field. They also experiment with cross-section lines and determine where they would create a cross-section of their own field map area.
2. Next, we review how to use stereonets to find the true dip of a bed in the case that you are unsure about the surface you measured (in the field we discuss that field data can and should include uncertainty and that if they come across a surface they want to measure but are unsure about the true dip direction, they can take a few measurements on the plane which can later be corrected in the lab with a Stereonet – something we already practiced in the lab).
3. Then, we consider another form of apparent dip – projecting orientation data onto a cross-section line. We use the Apparent Dip module in Visible Geology to convert dips that will be used in the proposed cross-sections.
4. Finally, the activity ends with the Stereonet module to find the orientation of the fold axis from the field data they collected.
   Depending on how much extra experimenting students may want to do, the activity should take ~3 hours.
   Attachments (supporting materials) include a screenshot from the geologic map of the area where we do the field trip, field photos showing what the fold looks like in the field area, and an example of the completed activity (student work).

Visible Geology teaching activity_post-trip_fold_deformation_analysis.docx (Microsoft Word 2007 (.docx) 6.9MB May15 26)

Visible Geology Teaching Activity - Post-trip Fold Deformation Analysis.pdf (Acrobat (PDF) 525kB May15 26)

Visible Geology learning activity_geologic_map_field_area.docx (Microsoft Word 2007 (.docx) 2.7MB Apr23 26)

Field Photos_VG_posttriplab.docx (Microsoft Word 2007 (.docx) 4.7MB May1 26)

PostTripFolds_Example_studentwork.docx (Microsoft Word 2007 (.docx) 4.2MB May1 26)

• To save and share their work in Visible Geology, students are encouraged to log in with their Google Account.

The lab activity includes reflection questions and required screenshots of student experiments. These are graded on a point scale (noted for each question on the activity).

• Geologic map on the National Geologic Map Database
• Rule of Vs teaching activity
• Visible Geology — Website with the Visible Geology web-based application
• For tips, tricks and how-to videos for using Visible Geology, check out the Visible Geology Help & Resources.