Deep Blue October Sky and Fossils - Walker County

In September, the Alabama Paleontological Society (APS) took a field trip to look for rocks and minerals but on October 17, 2020, it was back to fossils. It was a spectacular fall day with a bright blue sky, marked by only a few contrails, and a few areas of early morning frost scattered around north Alabama. Temperatures rose from the thirties into the sixties by afternoon and the low October sun provided a good grazing angle to see trace fossils. The site yields Pennsylvanian Age fossils from the Pottsville formation approximately 310-315 mya. We had a group of about 20 individuals excited about getting outdoors and filled with the anticipation of finding fossils. Not even COVID could dampen spirits, though all appropriate precautions and social distancing were in effect. Weeds, that had taken over the site during late summer, were rapidly subsiding as the dry coolness of fall was taking its toll on them. The decreasing weeds coupled with the cool temperatures on Saturday made both finding and splitting promising rocks less challenging and a number of wonderful finds were made.

Fossils discoveries included a wide variety of plant fossils, invertebrate trace fossils, and vertebrate trace fossils pictured below.

First, the plant fossils - there were a couple of exceptional plates containing multiple seed fern seeds (Trigonocarpus) and pollen organs. Additionally, a calamites pith cast, a horizontal section of a lycopod trunk , and other plant fossils were found.

(trigonocarpus/pollen organs, multiple trigonocarpus)

(calamites, lycopod, cone/bark?)

There were plenty of interesting invertebrate trace fossils found. These included Rusophycus (attributed to arthropods/trilobites), the chevron shaped Protovirgularia, Arborichnus, Kouphichnium (attributed to horseshoe crab), Treptichnus, and Diplichnites (attributed to centipede/millipede).

(rusophycus, protovirgularia, and arborichnus)

(kouphichnium, treptichnus, and diplichnites impression/counter-impression)

Finally, with some persistent work, there were quite a few tetrapod tracks and trackways discovered as well. Here are some of the tetrapod tracks found:

Once again this world class fossil site, yielded its world class trackways along with many other wonderful finds. As the COVID pandemic relentlessly marches on, we are fortunate to have a hobby and a place like this that affords everyone the opportunity to go outside, be safe and spread out, and do something so enjoyable!