The Friday, July 2nd, 2004 edition of The Reader featured an article titled "The Vanishing Mother Lode of Mazon Creek". The full text of the article is available online. Unfortunately, it doesn't include the pictures. This article was written by Mike Sula, no relation to long time ESCONI member Rob Sula. The article does a great job with the history of Mazon Creek fossil collecting. Many of the colorful characters were interviewed for the piece and some were ESCONI members. Some even contributed specimens for the animal book "The Mazon Creek Fossil Fauna" by Jack Wittry, written in 2012.
In the spring of last year Tom Testa made the painful decision to sell off a piece of his legacy--a 300-million-year-old fossilized chiton called Glaphurochiton concinnus, an oblong mollusk whose modern relatives graze on algae that cling to wave-swept rocky shores. Back then, in the middle Pennsylvanian period, Testa's chiton crept along the muddy floor of a shallow inland sea whose long northern coastline arced through what is now Kankakee, Will, and Grundy counties, about 50 miles southwest of the Loop.
Testa has several dozen chitons in his enormous fossil collection, most plucked from piles of discarded shale at a former strip mine near Braidwood. The mine was called Pit 11, and it's the most important of a group of fossil sites in the area, collectively known as Mazon Creek after the tributary of the Illinois River where the fossils were first discovered in the mid-19th century. Mazon Creek fossils are unique. They're well preserved and unusually diverse, and many have few relatives in the world fossil record. There are mollusks, plants, arthropods, fish, amphibians, and lots of weird soft-bodied invertebrates, which are especially important because the fragile creatures had no hard parts and therefore didn't fossilize easily.
More than 300 animal species and 200 plants have been identified from the Mazon Creek area, evidence that in the Pennsylvanian period northeastern Illinois teemed with life. Mazon Creek is known as one of the world's finest Lagerstatten--which, loosely translated from German, means "mother lode" and is used to describe a fossil fauna so well preserved and diverse it tells a nearly complete tale of what life was like when the creatures were alive. In his 1989 book Wonderful Life Stephen Jay Gould called Mazon Creek one of the three greatest LagerstŠtten of the Paleozoic era, the 345-million-year geologic period that begins with the first explosion of multicellular life and ends with a mass extinction just before the rise of the dinosaurs.
