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 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.
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.
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.
A view to the south-southwest on the big outcrop at Hidden Rock Park (2019).
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.
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.
It takes teamwork to measure the orientation of foliation at Hidden Rock Park (2014).
View of a sub-horizontal (nearly flat) part of the big outcrop at Hidden Rock Park. Hammer is ~40 cm in length.
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?
A view to the northeast on the big outcrop at Hidden Rock Park (2018).
Up-close with the bedrock at Hidden Rock Park (2019).
Standing tall at Hidden Rock Park (2005).
Hooray for the outcrop worksheets! Katie Valery at Hidden Rock Park (2016)
Post-geology playtime on the swings at Hidden Rock Park (2018).
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