Geological Field Tripping in Cyberspace

Early April is the time when my Earth Structure & Dynamics class ventures to the Appalachians for a weekend of learning and intellectual companionship.  I’ve reported on these academic adventures in this blog many  times1. Over the course of two days we roll across Virginia, from the Shenandoah Valley to the Blue Ridge and out into the Piedmont. We make observations and do geology at dozens of outcrops that range from the spectacular to the subdued. We camp in the Blue Ridge foothills — invariably the group camping and fine dining prove to be both positive and memorable bonding experiences.

Montage of 3 field trip scenes

Montage from the 2017 – 2019 Earth Structure & Dynamics class field trips. The 2018 class is all smiles in front of a spectacular outcrop at the Ragged Mountain Reservoir in the Blue Ridge. The 2017 class deep in thought at a morbid little outcrop in the Scottsville Mesozoic basin. The 2019 class enjoys lunch while in the field. It’s hard to social distance on these field trips.

The Spring 2020 semester is unlike any that has come before, and as a consequence of finishing the semester’s coursework remotely there is no Appalachian field trip this spring for my Earth Structure & Dynamics class. It’s a tangible loss, as it’s difficult to replace the learning packed into that field trip.

But we’re not giving up, the 2020 Earth Structure & Dynamics class is going on a digital field trip to one of the classic stops that we’ve visited for nearly two decades.

To be clear, I’ve yet to be convinced that virtual field trips can satisfactorily take the place of the real thing. The primary learning objective for our weekend class field trip is to practice doing geology in the field. To achieve our goal we make repeated observations and measurements, discuss our interpretations while standing at the outcrop, and learn from our mistakes. Doing geology in the field is difficult, and practice is important.

Google Earth image of Hidden Rock, Park Virginia with bedrock outcrops highlighted Our destination for this digital trip is Hidden Rock Park near Goochland. This former landfill was turned into a county park in the late 1990s. As the site was graded to construct baseball and softball fields, large expanses of the bedrock were exposed. Bedrock outcrops are far and few between in the eastern Piedmont and Hidden Rock Park serves as an important destination for William & Mary Geology field trips.

Had we visited Hidden Rock Park, the students would have poured forth from the vans, and working in teams examined the outcrop and tackled a set of questions posed on the ‘always popular’ field worksheets.Worksheet for the geology questions at Hidden Rock Park, VA. Identify the orientation of foliation at 5 or 6 locations on the big outcrop. Is the foliation folded? Is that significant? Why? What feature is exposed at Point X? How much strain have these rocks enjoyed? Estimate the bulk strain ratio for these rocks. Circle your preferred estimate. R5=1.1 R5=1.5 R5=2 R5=4 R5=10 Plot your estimated bulk rock strain ellipse in the space below (properly oriented with an appropriate aspect ratio).

What follows are a set of pictures (taken over the past 15 years on W&M field trips) from Hidden Rock Park that might be serviceable enough to answer the questions on the worksheet.

Students on an outcrop at Hidden Rock Park.

A view to the south-southwest on the big outcrop at Hidden Rock Park (2019).

Small view of an outcrop at Hidden Rock Park

View of a sub-horizontal (nearly flat) part of an outcrop at Hidden Rock Park. What rock types are present? Red pocketknife is ~10 cm in length.

Outcrop photo of boudins at Hidden Rock Park.

View of a sub-horizontal (nearly flat) part of an outcrop at Hidden Rock Park. What structures are X? Red pocketknife is ~10 cm in length.

Students measuring a geological structure at Hidden Rock park.

It takes teamwork to measure the orientation of foliation at Hidden Rock Park (2014).

Photo of outcrop with folded and boudinaged pegmatite dike.

View of a sub-horizontal (nearly flat) part of the big outcrop at Hidden Rock Park. Hammer is ~40 cm in length.

W&M students conducting strain analysis at Hidden Rock Park.

A view to the south-southwest on the big outcrop at Hidden Rock Park (2013).
What are the prominent features that are well exposed here?

Broad view of the big outcrop at Hidden Rock Park.

A view to the northeast on the big outcrop at Hidden Rock Park (2018).

Large boudinaged pegmatite at Hidden Rock Park.

Up-close with the bedrock at Hidden Rock Park (2019).

Students on an outcrop at Hidden Rock park.

Standing tall at Hidden Rock Park (2005).

W&M student on the outcrop at Hidden Rock Park.

Hooray for the outcrop worksheets! Katie Valery at Hidden Rock Park (2016)

W&M students on the swings at Hidden Rock Park.

Post-geology playtime on the swings at Hidden Rock Park (2018).

Lunchtime scene of students eating sandwiches and other picnic lunch fare sitting at picnic tables in a covered picnic area.

Chow time at Hidden Rock Park (2019).

Feel free to answer some of the worksheet questions and join our class conversation. Comments from everybody out there in learning land are most welcome.

I’ll follow up with answers from our field observations in a few days and summarize what we have learned from the bedrock and structures at Hidden Rock Park. Then we’ll take that next step and relate our local observations to broader regional questions about the tectonic history of the Virginia Piedmont.


1 Here’s the roster of past blog posts about the Earth Structure & Dynamics field trip

2019- Neoacadian Poets in the Blue Ridge

2017- Explorations in Time-Depth Space: The Earth Structure & Dynamics Field Trip

2016- A Hard Freeze in the Basement: The Earth Structure & Dynamics Field Trip

2015- Over the Hills and Far Away: The Earth Structure & Dynamics Field Trip

2014- 50 Hours in the Field: The Earth Structure & Dynamics Field Trip

2012- A Mobile Mob: The Earth Structure & Dynamics Field Trip

Categories: Academics, Faculty & Staff Blogs Tags: , , , , ,
34 Comments
  1. Sarah Snipes
  2. Lindsay Moller
  3. Naa-Kwarley Quartey
  4. Leah Green
  5. Danni Riggs
  6. Female Meat Brick
  7. Coffey Man
  8. Stanley
  9. Dorian Miller
  10. Tianchen Shi
  11. Olivia Pearson
  12. Meg Taylor
  13. Mahina Robbins
    • Mahina Robbins
  14. Cameron Clarke
  15. Gil Espenshade
  16. Greta Mattheis
  17. Paul "Chert" Volante
  18. Lee
  19. Haley Meyrowitz
  20. Arthur Keith
  21. Mikayla Huffman
  22. Terri Zach
  23. Bel Liscomb
  24. Breanna Maldonado
  25. Tim Terlizzi
  26. Johnny Peters
  27. Melanie Strik
  28. Olivia Falb
  29. Neel Simpson
  30. Chris Pardo
  31. Kathleen Chellman
  32. Leah Earnest
  33. Chris Bennett

Leave a Comment

Your email address will not be published. Required fields are marked *