This is Mazon Monday post #267. What's your favorite Mazon Creek fossil? Tell us at email:[email protected].
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The spring trip to the Danville Spoil Pile was held on Satuday, April 26th. The day started out overcast and chilly with temperatures in the mid-40s and fairly brisk winds. By the end of the trip, the sun was out and it had wamed to the mid-60s... perfect weather for some fossil prospecting. This is our ninth trip here. It's a long drive from the Chicago area, but well worth the time. Extraordinary specimens are found each time.
The spoil pile dates back to around the turn of the 20th century. The Dering Coal Company opened the mine in 1904, and it operated until 1946 under various owners, including the Peabody Coal Company, which managed the mine from 1916 to 1944. The shale pile is Pennsylvanian in age—approximately 305 million years old—making it about 2.5 million years younger than Mazon Creek's Colchester Coal No. 2. The contents of the spoil pile are problematic and consist of the Energy Shale (Anna Shale?), which lies just above the Herrin No. 6 coal seam and the Farmington Shale, which is the shale member associated with the Danville Coal No. 7. The Danville coal is about 100 feet below the surface, while the thicker Herrin coal is an addition 100 feet deeper. The plant compressions as well as concretions can be found in the spoil pile. At some point, spontaneous combustion occurred, transforming portions of the gray shale into "Red Dog" shale. For a more complete history of the mine and the ESCONI Herrin Coal Fossil Guides, see Mazon Monday #86 and the ISGS Guidebook here under "Stop 6.".
Scenes from the spoils
Fossil specimens
As usual, Andrew Young took photos of interesting specimens at the end of the trip.
Lepidostrobus cross-section, found by Anthony Friend
Odontopteris subcuneata, found by Keiichiro Susuki
Calamites cisti with concretion, found by Anthony Jasper
Alethopteris gibsonii, found by Keiichiro Susuki
Danaeites emersonii, found by Anthony Jasper
Lepidostrobophyllum lanceolatus, found by Jennifer Dilloon
Decorticated lycopsid stem, found by Steven
Lepidodendron sp., found by Gretel Monreal
Caulopteris sp., found by Steve Buss
Annularia inflata with Cyathocarpus arborea, found by Gretel Monreal
Calamites with ovipositional scars, found by Ben Riegler
