Our program this month will be presented by John Catalani. His talk is entitled: The Deicke Outage: A Midwest Extinction Event.
Although controversial, the faunal outage at the end of Platteville (Upper Ordovician) deposition has been explained by the in-fall of volcanic ash (Deicke Ashfall) during the Taconic Orogen. During this violent period in Earth history, intense volcanic activity sent enormous amounts of volcanic ash into the atmosphere. Since most of Laurentia (NA) was in the southern hemisphere, the SE Trade Winds carried this ash into eastern and central Laurentia. This ash weathered into K-bentonites present today in Ordovician rocks. Over 60 bentonites have been identified with the Deicke and Millbrig the most prominent. Represented now by the 5-10 cm thick Deicke K-bentonite, the ~30 cm of original volcanic ash, as the theory goes, would have suffocated the substrate of the Ordovician Ocean killing the inhabitants. The program covers the origination of the bentonites, the Deicke and Millbrig bentonites in detail, and the environmental effects resulting from the ash fall. Also discussed are alternatives to the ash-fall explanation for the faunal outage. Photos of fossils both pre-Deicke and the several recovery faunas will be shown. A possible second outage and its recovery fauna (Stewartville Bed) is also covered. Specimens from all three recovery faunas will be displayed.
John has a BS from Illinois State University with an MS from Indiana State University. He has taught science for 32 years at Downers Grove South High School (suburb of Chicago). John is a serious amateur and like many in the Dry Dredgers has worked with professional paleontologists for many years. He has participated in several professional GSA national/sectional meetings and several NAPC meetings. John published an Ordovician nautiloid range chart for MN Geological Survey RI 35 in conjunction with the 1987 North-Central GSA meeting. He was a long time contributor to PRI's American Paleontologist from 1995 to the last issue in 2012 by authoring the "An Amateur's Perspective" column. John was honored by PRI by being awarded the 2000 Katherine Palmer Award.
TIME: 8 pm
DATE: Friday, September 25,
2026
PLACE: Room 201, Braunstein Hall, UC Main Campus,
Clifton
SIMULCAST: via Zoom
- Link included in the paid members PDF version of The Bulletin
Meeting Attendance Attendance at UC was good at our May meeting with 20 on Zoom and 31 in-person.
Cincinnati Magazine The October issue of Cincinnati Magazine will feature three articles of interest to our members. One article is about the Dry Dredgers, one article is about fossils and the third is about the geology of this area. Input for these articles was supplied by Professor Carl Brett, Kyle Hartshorn and Jack Kallmeyer. Kyle will be providing some of his artwork. Bill Heimbrock, Ron Fine and Jack Kallmeyer provided meeting and field trip photos. Specimens used for the fossil article photo were provided by Ron Fine, Nikki Zehler and Jack Kallmeyer.
PayPal We are happy to announce that PayPal is now available to pay your dues. The Dry Dredgers website has been updated to show this as a payment option. See additional information later in this bulletin.
Secure Website The Dry Dredgers website has now been upgraded to secure status. Prior to this upgrade, search engines were showing our site as not secure making some searchers shy away from accessing our content.
Parking Passes New parking passes were obtained from UC by Kyle Hartshorn. These are to be used when parking in the Clifton Lots off Probasco street on the corner of MLK and Clifton. Passes will be available to members from Kyle or Jack in room 201.
Election of Officers The annual election of officers was held at the May meeting. The exisiting officers were elected for another term and all committee chairs will return.
The September Meeting will be held at the University of Cincinnati, 201 Braunstein Hall.
Beginner's Class
by Lincoln Schumaker
TThe Beginners Class will be conducted from 7:15 PM to 8:00 PM on September 25th. It will be held before the general meeting in Room 300, Braunstein Hall, one floor up from our regular meeting room. It will be in-person only. No remote Zoom.
Lincoln’s program will be: An introduction to the geologic timescale.
It has been three years since the Dry Dredgers visited this Northern Kentucky
Byway; during that trip, we had local television coverage! (If you are
interested in viewing it, here is the link:
https://www.fox19.com/2023/05/11/cincinnati-dry-dredgers-bring-paleontology-public/.)
It is a wonderful opportunity to explore the Kope formation on multiple levels
and finds from trilobite burrows to a variety of specimens will be found.
We will meet at the shopping center at Cross Roads Blvd, set our odometers, and then visit at least three strategic spots along the way. Field guides will be distributed to attendees; stops will be made at locations with sufficient shoulder parking and with safe access areas.
The date is Saturday, September 26th; departure time is 10:00, so arrive early and we can depart on time. Directions are in the PDF version of the Bulletin that is emailed to dues-paying members. If you would like to come on this field trip and are not a member, you can join and pay your dues online RIGHT HERE.
As always, the trip is rain or shine. Hiking boots are recommended, as areas may be a bit muddy – but that’s part of the fun to come home dirty and announce to the family: “Look what I found!” (Note: your respective family’s enthusiasm may vary . . . ) See you there!
More interesting and informative articles, along with color illustrations is available in the full E-Bulletin that was emailed to dues-paying members.
The Dry Dredgers and individual contributors reserve the
rights to all information, images, and content presented here. Permission to
reproduce in any fashion, must be requested in writing to admin@drydredgers.org
.
www.drydredgers.org is designed and maintained by Bill Heimbrock.