There will be a field trip to the Starved Rock Clay Pit on Saturday, July 24, 2021 from 8 AM to noon. The trip is shared with the Lincoln Orbit Earth Science Society (LOESS) of Springfield. The clay pit is located just south of Starved Rock State Park.
Other than the glacial overburden, everything at the clay pit is Pennsylvanian. From top down the layers are:
Mecca Quarry Shale - Black shale, hard.
Francis Creek Shale - Mudstone from deltaic deposits
Colchester No. 2 coal
Underclay - paleosol where the plants that made up the coal were rooted
This location produces pyrite balls, pyritized wood, occasional vertebrate and invertebrate fossils in the black shake, and Mazon-like concretions. From my experience, the concretions do not split like typical Mazon concretions, but tend to degrade to flakes when subjected to freezing/thawing. The entry road is made with rock from the nearby Lone Star (Buzzi-Unicem) quarry (LaSalle Limestone and gray shale).
Rules:
- Everyone in your party must be at least 18 years old and an ESCONI member (unless you're a member of LOESS) by July 21, 2021. The ESCONI attendance limit is 20.
- Meet at the entrance to the clay pit by the buildings. The entrance is on the east side of Rt 178 just north of Rt 71. It’s not right at the corner, but just a little closer to the park. Take a look on satellite view and you’ll see a couple buildings. We’ll drive between those and around the north tip of the pond to go back to the clay pit area closer to Rt 71. Please don’t use the other roads on the property. This is private property.
- Bring and wear a hard hat and safety vest. Boots are required as this location can be very muddy. If you plan to hammer on rocks then bring and wear eye protection. This is a big place, and a wagon or cart can be helpful.
- This is not a hard-rock quarry, and the walls are not high, but exercise caution near any wall. If it looks unstable, don't go near it. Stay away from any equipment or cables.
- The commercial product here is clay removed from pits in the quarry floor. These pits accumulate water. You must not go in the pits or the water. The mud in and around the pits can suck you in and not let go!
- If the entry road is in bad shape or there has been recent rain, vehicle access may be limited. We'll find out when we get there. If there is too much rain in the days leading up to the trip we will cancel.
- Please review the ESCONI Code of Ethics and Conduct on the website. It applies to field trips like this one. An ESCONI liability waiver will be sent to those that sign up. You don’t need to sign it – just know what you’re agreeing to by attending.
Sign up by sending me (Dave) an email at [email protected] giving the number of ESCONI members attending and their names. I will confirm by return email within 24 hours. If you don't hear from me in that time, send it again!
