Thursday, August 20, 2026 | Starting: 02:00 PM
TALKS
Travel back hundreds of millions of years to a time when Door County was covered by a warm, shallow sea! Join Naturalist Coggin Heeringa for a fascinating program exploring the ancient Silurian seas and the fossils they left behind.
Coggin will guide participants through Door Countys deep geological past, explaining how coral reefs, marine invertebrates, and other sea life flourished here during the Silurian Periodlong before dinosaurs or even land plants existed. Learn how fossils such as corals, brachiopods, and crinoids formed, where they can still be found today, and what they reveal about Earths changing climate and environments over time.
This accessible and story’rich program will help you recognize common local fossils and understand their connection to Door Countys distinctivedolomite bedrock, escarpment, and shorelines. Perfect for curious beginners and seasoned rock hounds alike, this talk brings ancient geology to life through science, history, and hands’on discovery. Join us to uncover the fossilized remains of a long’vanished sea and gain a deeper appreciation for the ancient forces that shaped the peninsula we know today.


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