Earth Science Club of Northern Illinois

Fossil Friday #330: Mazon Creek in the Illinois State Fair 4H

ESCONI Junior Luke Schallhorn had his Mazon Creek Fossils 4H geology project selected as a delegate from Marshall-Putnam County to the Illinois State Fair! It was on display on Sunday, August 16th, 2026. Maybe, you saw it?!?

Throwback Thursday

Throwback Thursday #330: All Illinois Rock Swap and Silent Auction

August 28, 2026 will mark the 50th Anniversary of the “All Illinois Rock Swap and Silent Auction”. It was held on August 28th and 29th, 1976 at the College of DuPage in Glen Ellyn, IL. The event was held in Parking Lot K. Long-time ESCONI member Rich Rock was Chairman. And really, who has a better name for than him to be involved in an event like this? Here is a photo of him and his grandson Pete at last year’s ESCONI Rock Swap.

Field Trips

ESCONI Field Trip to Bellevue, MI Quarry on Saturday, September 12th, 2026

A field trip to a quarry in Bellevue, MI is scheduled for Saturday, September 12th, 2026. This is a joint trip with the Kalamazoo Geological and Mineral Society (KGMS), and will be led by KGMS members. There is space for 15 ESCONI members. The trip will be from 9:30 AM ET to 2:30 PM ET. Note the time change for those coming from Illinois! The quarry exposes the Bayport Limestone (Mississippian/Lower Carboniferous). Minerals (calcite, pyrite, chalcopyrite, etc.) and fossils (coral, brachiopods, shark teeth, etc.) can be found. You must register to go on this trip. See rule 8 below for instructions. This is…

Calendar of Events

Reminder! 2026 ESCONI Rock, Mineral and Fossil Swap and Sale – August 15, 2026 at College of DuPage

ESCONI is sponsoring a rock swap and sale event on August 15, 2026 at College of DuPage in Glen Ellyn. The location is Parking Lot 4, south of the Health and Science Building, and adjacent to the prairie.

Mazon Creek, Mazon Monday

Mazon Monday #335: Richardson Collecting at Pit 11 in 1974

A few years ago, Charlie Shabica donated a collection of historical documents to ESCONI, and these photographs were among the materials. They document a Mazon Creek field trip in July 1974 led by Eugene Richardson Jr., Curator of Fossil Invertebrates at the Field Museum.

Around the Web

Behold, The World’s Oldest Amber – a Record of a World 385 Million Years Ago

Science Alert has a story about the discovery of the oldest known amber. The amber dates to the Middle Devonian Period, some 385 mullion years ago and about 65 million years older than the previous record holder. Amber is fossilized tree resin, so land plants needed to evolve before amber was possible. This particular amber was found in a coal deposit in northwest China. We tend to think of tree resin as an ancient, fragrant defense against munching insects – one that fends off pests and scabs over the wounds left by their voracious mandibles. But a new discovery suggests that these viscous…

Around the Web

Rock River Valley Gem and Mineral Society Rock Swap – Saturday, September 12th, 2026

Rock River Valley Gem and Mineral Society Rock Swap – Saturday September 12, 2026

Fossil Friday, Mazon Creek

Fossil Friday #329: Pit 11 Roachoid!

This beautiful roachoid comes from ESCONI President Chris Berg. He collected it from the Pit 11. It opened up recently via the freeze/thaw method. Thanks for sharing, Chris!

Throwback Thursday

Throwback Thursday #329: Looking Back At ESCONI For July/August 2026

The newsletters are typically sparse in the summer, but here is a bit of ESCONI history for your summer reading pleasure. 25, 50, and 70 years ago…

Around the Web

Storms that built a graveyard: ancient monsoons created a spectacular dinosaur fossil site

The Conversation has an interesting post about an important fossil site in northeastern Italy. The Villaggio del Pescatore site dates to 80 million years ago, which was near the end of the Cretaceous Period. Fossil animals found in the locality were swept in to the area by monsoon rains and tropical cyclones. Dinosaurs, crocodiles, and plants were preserved in river mud on a tidal flat. More details can be found in the paper “Climate-extreme-driven genesis of a Cretaceous dinosaur Lagerstätte” in the journal ScienceDirect. My colleagues and I have published a new study that reconstructs the violent tropical climate behind the Villaggio del Pescatore…

Uncategorized

The Best Forest Preserves Near Chicago for Hiking, County by County

Sam S., the editor of the Chicago Signal, sent us a link to this article about hiking the forest preserves in the Chicago area. There are tips about Cook County and all the surrounding counties, even Midewin in Will County. Summer is slowly slipping away… get out there and enjoy some nature! The Chicago Signal has guides about Food & Drink, Things To Do, Real Estate & Moving, and Outdoors & Recreation. Check it out! There are roughly 70,000 acres of forest preserve in Cook County, another 26,000 in DuPage, and 31,600 across 65 sites in Lake. You do not…

Mazon Creek, Mazon Monday

Mazon Monday #334: Mariopteris lobatifolia

Mariopteris lobatifolia is one of the rare species of Mariopteris. Its pinnules have a very distinctive wing-like shape. See Mazon Monday #181 for the most common variety of Mariopteris, Mariopteris nervosa.

Around the Web

PBS Eons: How Pangea Upended Life on Earth

PBS Eons has released their TV series about Pangea! Check out Episode 2 on pbs.org. In the Late Carboniferous Period, predatory amphibians and giant arthropods ruled the swamps. But ancient seed plants and amniotes were evolving adaptations to drier climates. These will help them thrive on Pangea in the Permian Period to come. This is the first our our six-part series on life and death during the Permian period. Episode 2 is available right now! Watch the full series on the PBS App https://to.pbs.org/EonsApp You can also watch on PBS.org – in particular if you’re outside of the US: https://pbs.org/eons…

Around the Web

Field Museum – Legendary Late Hours – August 11th, 2026 – Riot Fest Takeover!

The Field Museum is holding a “Riot Fest Takeover” on August 11th, 2026 from 5-9 PM. Enjoy extended museum hours from 9am to 9pm, last entry at 8pm. The Field Museum and Riot Fest are partnering up for a righteous Museum takeover from 5pm-9pm on August 11th, complete with music and some seriously sick specimens, to get you geared up for Riot Fest 2026. Our fossils are older than dirt and larger than life. Come dig in with the scientists that dig up our fossils. This event is part of our Legendary Late Hours series, included in general admission. During…

Fossil Friday, Mazon Creek

Fossil Friday #328: A Pit 11 Octomedusa piekorum

Well, we know how Alan Keith is spending his summer vacation… freeze/thawing his Mazon Creek concretions. Although, probably not out in the hot Texas sun. Alan had this nicely detailed Octomedusa piekorum (see Mazon Monday #54) open up recently.

Throwback Thursday

Throwback Thursday #328: Go on… Introduce yourself, tiny frog

The Field Museum made an intriguing historical post to LinkedIn last week. It was a meet-and-greet between two frogs…

Calendar of Events, Field Trips, Mazon Creek

ESCONI Field Trip to Braceville, IL for Mazon Creek Fossils – Saturday, August 29th and Sunday, August 30th, 2026

Braceville Field Trip Rules for August 2026 The ESCONI field trips to Braceville for Mazon Creek fossils are set for August 29th and 30th, 2026 from 9 AM to 3 PM. You can attend one or the other, but not both days. There is an attendance limit of 60 people each day. You must register to go on this trip. See rule 6 below for instructions. This is the ONLY way to register. If you are sick, have any symptoms of Covid-19 or have recently tested positive, DO NOT COME. Meet at 9 AM at the entrance to the collecting site…

Around the Web

PBS Eons: How the Tibetan Plateau Created the Ultimate Cat

PBS Eons has a new video. This one is about the evolution and migration of Homotherium, a large saber-tooted cat that lived on the Tibetan Plateau. How did Homotherium evolve to be so successful, and so different from basically all other cats, living and extinct? Well the answer may lie in a huge geological event: the rise of the Tibetan plateau.

Mazon Creek, Mazon Monday

Mazon Monday #333: Interesting Pennsylvanian Fossil Sites – Okmulgee, Oklahoma

Way back in Mazon Monday #10, we referenced the paper “Mazon Creek-Type Fossil Assemblages in the U.S. Midcontinent Pennsylvanian” written by G. C. Baird, S. D. Sroka, C. W. Shabica, T. L. Beard, A. C. Scott and F. M. Broadhurst in October 1985. The paper lists and discusses the various Pennsylvanian fossil sites known to produce fossil bearing concretions similar to what is found at Mazon Creek. Although the list of concretionary sites has grown since the paper was published, it’s still relevant and a good read. Check it out, you can download it from ResearchGate.

Around the Web

Rare Pompeii Ceiling Is Restored From Fragments, Depicting Scene From Myth

The New York Times has an interesting article about the restoration of a fresco at Pompeii. The fresco was restored from hundreds of plaster fragments recovered from the ruins of a house. The house, now called the “House with the Bakery”, was discovered by researchers in 2023. The fragments of plaster were like a “magnificent” puzzle. The scene depicts Dionysus and Ariadne. In Greek mythology, Dionysus is the god of wine, festivity, and revelry, while Ariadne, the daughter of King Minos of Crete, famously helped the hero Theseus navigate the Labyrinth and defeat the Minotaur. The vault is a rare…

Saturday, July 11th	Field Trip to Mount Orab for Ordovician Trilobites Details were sent in an email.
Saturday, August 15th	ESCONI Rock, Mineral, and Fossil Swap College of Dupage – 9:00 AM – 3:00 PM. Details here.
No meetings until September	General Meeting
No meetings until September	Paleontology Study Group
No meetings until September	Junior Study Group Meeting
No meetings until September	Mineralogy Study Group

ESCONI Rock, Mineral and Fossil Swap and Sale!

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