When Lake Erie Was a Tropical Sea
You're rolling through gentle, wooded country here near Cascade Creek, where the land rises and falls in modest swells. This is the Appalachian Plateau, where old sedimentary rocks form the bones of these hills. The creeks have carved their way down through layers that look unremarkable at first glance, just gray-brown stone and shale, but what you're seeing is something extraordinary: the floor of an ancient ocean, turned to stone.
These rocks are Devonian, formed between 380 and 360 million years ago, part of what geologists call the Canadaway Group. Back then, this whole region sat beneath a warm, shallow sea that stretched across much of North America. The Catskill Delta was building eastward, dumping sediment from mountains that once rivaled the Himalayas. You're looking at shales and siltstones, the muds and sands of that ancient seafloor, compressed over unimaginable time into solid rock.
Now here's what makes this area special: scattered through these rocks, especially in the creek beds and roadcuts, you'll find the stone ghosts of coral reefs. Not modern reefs like you'd see in the Caribbean, but something older and stranger. These were built by rugose corals, animals that went extinct 250 million years ago, and by creatures called stromatoporoids, sponge-like reef builders that dominated Devonian seas.
Imagine that moment, 370 million years ago, when this reef was alive. Warm water, crystal clear, lapping over limestone platforms. Horn corals reaching upward, each polyp building its calcium carbonate home. Trilobites scuttling across the bottom. Primitive fish, the ancestors of everything with a backbone on land today, darting through the current. Then the sea retreats, rivers bury everything under mud, continents collide, mountains rise, and time does its patient work. The creatures become stone. The stone becomes hill country. And then you drive through, past signs for Cascade Creek, crossing directly over a world that predates trees, predates dinosaurs, predates almost everything we think of as life on land.
Stop at any creek crossing here and look closely at the rocks. Those strange circular patterns, those ridges and bumps? That's not just stone. That's time made visible.
| 01 | You're rolling through gentle, wooded country here near Cascade Creek, where the land rises and falls in modest swells. This is the Appalachian Plateau, where old sedimentary rocks form the bones of these hills. The creeks have carved their way down through layers that look unremarkable at first glance, just gray-brown stone and shale, but what you're seeing is something extraordinary: the floor of an ancient ocean, turned to stone. These rocks are Devonian, formed between 380 and 360 million years ago, part of what geologists call the Canadaway Group. Back then, this whole region sat beneath a warm, shallow sea that stretched across much of North America. The Catskill Delta was building eastward, dumping sediment from mountains that once rivaled the Himalayas. You're looking at shales and siltstones, the muds and sands of that ancient seafloor, compressed over unimaginable time into solid rock. | 1:02 | |
| 02 | Now here's what makes this area special: scattered through these rocks, especially in the creek beds and roadcuts, you'll find the stone ghosts of coral reefs. Not modern reefs like you'd see in the Caribbean, but something older and stranger. These were built by rugose corals, animals that went extinct 250 million years ago, and by creatures called stromatoporoids, sponge-like reef builders that dominated Devonian seas. | 0:26 | |
| 03 | Imagine that moment, 370 million years ago, when this reef was alive. Warm water, crystal clear, lapping over limestone platforms. Horn corals reaching upward, each polyp building its calcium carbonate home. Trilobites scuttling across the bottom. Primitive fish, the ancestors of everything with a backbone on land today, darting through the current. Then the sea retreats, rivers bury everything under mud, continents collide, mountains rise, and time does its patient work. The creatures become stone. The stone becomes hill country. And then you drive through, past signs for Cascade Creek, crossing directly over a world that predates trees, predates dinosaurs, predates almost everything we think of as life on land. Stop at any creek crossing here and look closely at the rocks. Those strange circular patterns, those ridges and bumps? That's not just stone. That's time made visible. | 1:01 |