On Saturday, September 19th, the whole team of students set off for the Rockford Quarry with Dr. Sedlacek leading the trip. As it was the second trip to the quarry, the team set off feeling prepared for the day since the contact had been identified.
Right off the bat, the team split into two groups. Carissa, Katie, Jessica, and Jose went off in search of any possible quarry pits that had been missed in the scouting trip. Later analysis of the land had revealed some topographical low points that were worth double checking. Unfortunately, those areas were natural hills and not a second pit to explore. At this point the four met up with the rest of the group who had reached an area of the quarry to start tracking the contact.
Right off the bat, the team split into two groups. Carissa, Katie, Jessica, and Jose went off in search of any possible quarry pits that had been missed in the scouting trip. Later analysis of the land had revealed some topographical low points that were worth double checking. Unfortunately, those areas were natural hills and not a second pit to explore. At this point the four met up with the rest of the group who had reached an area of the quarry to start tracking the contact.
When they reconvened, tasks were delegated. Bobbi, Carissa, and Katie helped Dr. Sedlacek locate the contact and verify that it matched what literature on the area had described as the resistant bed in the Cerro Gordo member of the Lime Creek Formation. As they worked through that process, the rest of the team set out collecting fossils. No one had to move more than a few feet to find fossils scattered throughout the area. This quarry contained brachiopods, bryzoans, crinoids, gastropods, along with a few less prevalent groups of fossilized organisms.
After a little while, Dr. Sedlacek and those helping her located a small section of the resistant band- contact the team was looking for. In appearance it wasn't all that different from the underlying and overlaying beds of rock with the exception of a higher prevalence of fossils. However, by the feeling the rock beds, they were very distinct. The underlying and overlaying layers were shale and, essentially, crumbled upon contact. The resistant bed was very hard and had a distinct texture.
With the contact rediscovered and verified, the team began the process of tracing it back to the area the team had intended to take samples from. By doing this, it could be confirmed that the samples were taken from the correct bed of rock rather than being taken from bed that was perceived to be the same bed.
This is when the majority of the traditional field work started. It was a learning experience for everyone, but it wasn't the only thing that the team members took away from the day.
"I learned how to use a Jacob’s Staff to measure distances up a rock wall. I also learned more about identifying the fossils from the Devonian Rocks and gained confidence in doing so" -Carissa
"Field work is tedious, but it wasn’t as intimidating as I had imagined. Once you got the hang of what you needed to do, it went by pretty quickly" -Jessica
"I learned how Geologists sample rock, and how they look for a certain kind of rock or shelf. We had to measure the shelf every 25cm and take samples of it. I learned that it’s a lot easier to make fractures in the rock in order to get a good piece that’s about the size of a fist, which is an ideal size for a sample. I also learned how to use a Jacob’s staff for the first time" -Brittnie
The process of tracing the layer around the quarry was quite an adventure. Using a Jacob's staff, the team would use one member to measure off height from the base of the quarry. While one student stood at the measured distances, other students checked the measurement to be as consistent as possible. And eventually, the team traced the contact around the quarry and verified that it was indeed the correct bed of rock to collect from.
Dr. Sedlacek taking detailed field notes of the area prior to sample collection
After the area was surveyed and recorded, the half the team went to work on rock collection. Based on the size of the area to work in, the team decided to rotate as to not get into each other's way. After that, there was not one person who didn't get a little muddy. The area the team collected samples in was characterized by primarily shale, and with the rain the night before, there were prevalent puddles and slick spots. Everyone had to be very careful in order to keep their footing and avoid getting soaked shoes.
The team worked from the start of a narrow gully to an exposed rock face at the end. The only places with viable samples were at the beginning and end of the gully which made the gully a bit of an obstacle to overcome. Similarly to earlier that day, students used the Jacob's staff to track the height changes through the gully to create reproducible results. In such a narrow gully, this was quite the challenge and actually resulted in the creation of a new form of exercise- field yoga.
Bobbi balancing herself on the side of the gully to use the Jacob's staff
After working in the gully, there was a general consensus about the hardest part of the day:
"The hardest part of the day was when we had to sample the rock on a slippery slope. I kept sliding, and there was a lot of mud that I was trying to avoid falling into" -Brittnie
"Correctly measuring out the vertical height of the rock, especially considering it’s very long slope" -Bobbi
"Measuring the incline of a very narrow gully" -Jessica
"I had an extremely hard time getting out in the mud" -Jose
"The hardest part of the day was trying to maneuver through the steep edges of the hills while trying to measure and collect rock samples" -Steven
Once that half of the team got through the gully, the teams rotated to finish off the sample collection. The last section of the rock collecting area was a near vertical rock face.
While the shale was slippery in this last section as well, the team got everything they needed. At the end of the day, the team walked away with bags of samples, a plethora of fossils, enough mud on their clothes to make plenty of mud pies, and smiles all around.
Each team member had different part of the day they enjoyed the most.
"I mentioned that the hardest part of the day was trying to maneuver through the steep hills; this was also the most exciting and fun part of the day" -Steven
"Finding nice sized fossils, and working as a team" -Brittnie
"Fossil hunting and identification. It was very easy to find fossils, but particularly exciting when you found a well-preserved one" -Bobbi
"I loved being out in the field, I had a great time when I found my first fossil" -Jose
"Oddly, sliding around on the clay" -Dr. Sedlacek
While everyone had a unique perspective, all of them were encompassed by a common theme: the experience of field work (whether it be the mud, the fossils, or climbing slopes) was something that could not be matched by anything in a classroom- not by a long shot.
"Getting to climb up the slopes to find the contact was fun. Collecting fossils was really cool too" -Katie