Our geology

The strata of Penn Dixie: Windom Shale, Tichenor Limestone, and Wanakah Shale.

Three hundred and eighty million years ago, Western New York was a very different place — both literally and figuratively! Situated approximated 20 degrees south of the equator during the Devonian Period, the region was a shallow marine environment that hosted many exotic — and now extinct — organisms. Trilobites, brachiopods, corals, crinoids, fish, and cephalopods ruled the tropical seas, while rooted plants and the first amphibians burst onto the relatively barren land.

It all came to a disastrous end approximately 360 million years ago, as environmental changes — brought on by unknown causes — triggered one of the Earth’s five largest extinction events. Globally, at least 75% of all species had disappeared by the end of the Devonian.

Some common Penn Dixie brachiopods from the original field trip guide.

The original Penn Dixie field trip guide — written by Jerry Bastedo in 1999 — features the history of our site as well as an introduction to common fossils. You can download the PDF here: Penn Dixie Field trip from 71st NYSGA 1999