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I found a possible millipede in my Mazon Creek freez thaw pile outside today!

I'm updating a display of Mazon Creek fossils that has been in our biology department for a long time. I would appreciate any help with identification and naming. (There were quite a few misspellings in the original display. I see one I missed - Asterotheca miltunii should be miltoni (or miltonii?))

I'm taking a feather from @Nimravis and starting a thread about repairing Mazon Creek fossils. I use the freeze/thaw method, but I do tap them lightly once in a while. That usually isn't what causes concretions to fall apart. Water creeping into the rock finds all the weak spots and sometimes a concretion basically shatters. Some localities are have hardier concretion than others. I have found that Pit 2, 3, and 4 have great preservation, but Shadow Lakes isn't referred to as Shatter Lakes for nothing. Super glue is nice, but I generally use Elmer's Glue as you can easily dissolve the glue in water and try again. Here is the first installment... a Macroneuropteris scheuchzeri from Pit 3. Collected last year during the construction on IL 129, but opened this year via freeze/thaw. I used Elmer's Glue on this one. Cheers, Rich

It has been a couple of years since we went last, but is it too late this year to head back out to Pit 11 area? We have always looked around Monster Lake. The finds are so so, but wondering if there is somewhere else we should try or just stick to that area. Thanks, Todd

Hello, I recently went to Mazon Creek for the first time. I have done some fossil hunting with my dad but really had no idea what we were doing. I found a couple other people searching for fossils and I joined them. Below is what I found. I know one is a Crinoid piece. The other two I am unsure if they are fossils. If anyone can give me some feedback, that would be great. As I said, I am new to the hobby so I was hoping to find others in the Mazon Creek area that would be interested in going on a trip there. If you are interested or have any advice you can give, that would be great.

The annual I&M Canal Corridor Fossil Trip was split between two weekends this year. Saturday, August 13th and Sunday August 14th, 2022 were family and beginner days, while more experienced collectors had their opportunities on Saturday, August 27th and Sunday, August 28th, 2022. From the look of what was found, the families barely made a dent in the supply of fossils. In case you are not familiar with the history of the site, the Kodat/Benson farm is designated as a National Historic Landmark in 1997. Statement of Significance (as of designation - September 25, 1997): The Mazon Creek Fossil Beds are important in the history of U.S. geology. When they were discovered in the mid-19th century, the beds provided the best and earliest representations of the oldest plants and animals known. Sites where fragile fossils are common and well preserved (here in distinctive ironstone nodules) are exceedingly rare. The Mazon Creek beds continue to be a prolific source of fossils. This trip is always well attended. The family and dinner event (August 28th) included an informative lecture by Andrew Young and Dave Dolak about the geology, history, and the fossils found at the site. There were quite a few opened concretions found on each day. The finds ranged from a shark tooth, to a huge lungfish scale, and many of the spectacular ferns common throughout the Mazon Creek fossil deposit. I saw many Fossil Forum people at the event. Please post photos to this thread. I gave most of my open pieces away, but will be adding any new fossils as my unopened concretions go through the freeze/thaw process. Please add yourself, if I have missed you. @deutscheben @connorp @bigred97 @Roby Here are a few photos over the 4 days.

Hello everyone! Today I ventured out to the Mazonia-Braidwood State Fish and Wildlife Area for my first time, and it was… something. This post is going to serve as both a journal of my day, and as a request for assistance as I try to figure out what exactly a concretion looks like. Once I got my permit outside the office (which is just down Huston Rd a bit from the IL-53 and Huston Rd intersection; this is for people like myself who struggled to find an address or location of the office), I headed to Mazonia south unit, where I went to fossil hunting site 3. There were not really any exposed rocks here, so I went deeper into the brush. I spent two hours picking up random rocks that looked remotely orange and red, until I realized that I was probably looking for the wrong types of rock in general. I had seen a ton of pictures online of concretions from Mazon creek, but all of them were of the fossils people found on the inside, which left me befuddled about what the outside looked like. I walked around until I found a place with cell service and planted myself on rock so I could watch a couple YouTube videos of people who had visited the area before. I learned a little about what I should be looking for, but I was still very confused. I managed to find the rock below, which looks vaguely like a fossil and gave myself some false hope, but I believe it’s probably just the way minerals formed on the rock that are deceiving: As morale dwindled, I made my way back toward the parking area and decided to walk a bit down the road. I found a neat little skull in a ditch as I was walking: As I kept going, I started stopping at some small exposures within a few feet of the road, and that is actually where I saw what I now understand to be the nodules I should be looking for. It was one of the two below: It made me feel a bit better that I found an actual concretion, as I went much of the afternoon without seeing any rock exposures. I have come to believe that fossil hunting site 3 may have a dearth of concretions, though I may be incorrect. Anyway, after finding the first concretion, I found a few similar rocks. However, I’m not entirely sure if they are potentially fossil containing material or if they’re just rock: They all have the dark red sections that I associated with iron, so I took them with. That is about the extent of what I grabbed that I thought were concretions, though I realize now that not all of those are even concretions. As I was wrapping up a mostly forgettable day, in the last roadside stop before my car, I came across this: I asked elsewhere on the interwebs and was informed that it might be a trackway, which I would think would be from an insect. However, if it is something else, please do let me know. Regardless, I was thrilled with this. I didn’t know what it was, but I did know it wasn’t something I had ever collected. In fact, today was the first day I have ever collected fossils from organisms that lived on land. It more than made up for the cold, gloomy weather and the disappointment I had experienced earlier. Just make sure to know generally what you should be looking for before you get there, unlike me. Now to my big question. How do I differentiate concretions from any regular old weathered rock? Are they typically round to some extent, as I see on others’ posts, or do they sometimes occur as jagged shapes? Are spherical rocks more likely to be regular rocks, whereas concretions are generally flatter in a dimension? I understand their shapes and sizes are diverse, but are there any patterns that tend toward a concretion over any a generic rock? As I finish up this topic, I do have one question about the two oval concretions I showed in my hand. Are the theoretical fossils inside the “egg” shape that lies inside the shell, or would they be on the outside of the egg shape? In other words, once I remove the rest of the shell from each of them, do I do the freeze-thaw cycles on the rock inside the shells? Thank you for reading and helping, and I apologize for all the questions!

I just had a concretion pop after thawing out today. Lo and behold, it actually has something inside. I’m not really sure what to make of it. Any ID help would be greatly appreciated. It’s about 1.5 x 2 inches. One wet and one dry picture

This I found only 1 size not sure if its anything or if it might be worth having someone clean it up. Thanks

https://royalsocietypublishing.org/doi/10.1098/rsos.210319 https://doi.org/10.1098/rsos.210319 Abstract: The Carboniferous Pennsylvanian-aged (309–307 Ma) Mazon Creek Lagerstätte produces some of the earliest fossils of major Palaeozoic tetrapod lineages. Recently, several new tetrapod specimens collected from Mazon Creek have come to light, including the earliest fossorially adapted recumbirostrans. Here, we describe a new long-bodied recumbirostran, Joermungandr bolti gen. et sp. nov., known from a single part and counterpart concretion bearing a virtually complete skeleton. Uniquely, Joermungandr preserves a full suite of dorsal, flank and ventral dermal scales, together with a series of thinned and reduced gastralia. Investigation of these scales using scanning electron microscopy reveals ultrastructural ridge and pit morphologies, revealing complexities comparable to the scale ultrastructure of extant snakes and fossorial reptiles, which have scales modified for body-based propulsion and shedding substrate. Our new taxon also represents an important early record of an elongate recumbirostran bauplan, wherein several features linked to fossoriality, including a characteristic recumbent snout, are present. We used parsimony phylogenetic methods to conduct phylogenetic analysis using the most recent recumbirostran-focused matrix. The analysis recovers Joermungandr within Recumbirostra with likely affinities to the sister clades Molgophidae and Brachystelechidae. Finally, we review integumentary patterns in Recumbirostra, noting reductions and losses of gastralia and osteoderms associated with body elongation and, thus, probably also associated with increased fossoriality.

Need an ID on this fossil fern from the Mazon Creek formation, please note, two pictures were taken in the dark with a flashlight

Last weekend, August 17th and 18th, 2019 was the annual I&M Canal Corridor Mazon River Fossil Trip. We were collecting Mazon Creek concretions on private property. The site is designated a National Historic Landmark and is a protected site. It's only accessible once a year by permission of the land owner. The weather was rainy in the morning for both days, but managed to clear up by 1:00, when the event began. On Saturday, Andrew Young gave an interesting lecture about the history and science of Mazon Creek fossils. He mentioned Lagerstatte, Cyclothems, Tidal Rhythmites, Braidwood Biota, and Authigenic Mineralization/Precipitation. How often do you hear those terms in one lecture? I have collected with Andrew for many years, he never fails to get you excited about collecting Mazon concretions. On Sunday, it was Dave Dolak's turn to give the opening talk. He covered the history and science from a slightly different view... also, interesting. Along with teaching geology at Columbia College in Chicago, Dave is known for his original music and songs on various Chicago subjects. Check him out on Youtube. Both speakers did a great job mixing personal experience with the actual science and history. This is a paid event and dinner is provided after collecting. The dinner is always excellent! Lecture photos. The first one is Anna Koval, President of the I&M Canal Corridor Association. Andrew Young Dave Dolak River Pictures Some already open concretions are the next post. BTW, there were a few fossil forum people there, @flipper559, @bigred97, and possibly others. Please speak up if you were also there.

The ESCONI fall field trip to Braceville, IL will be on September 14th and 15th, 2019. Come on out and stock up on Mazon Creek concretions to freeze and thaw this winter. We have two Braceville field trips each year, one in the spring and one in the fall. There is space to 50 people in each day. You do need to be a member of ESCONI to attend. That is a simple process on our website using PayPal. Send an email to fossil54@att.net to reserve a place! All the details are here: https://www.esconi.org/esconi_earth_science_club/2019/08/esconi-field-trip-to-braceville-il-for-mazon-creek-concretions-september-14th-and-15th-2019.html Cheers, Rich