(Isle la Motte, VT) Goodsell Ridge (Fossil)

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Gastropod and cephalopod fossils seen in Goodsell Ridge (near 44.8537, -73.3395), Monday Apr. 8, 2024, on Isle la Motte, VT.  Credits: Geo Field Report


Northern New England (VT, NH, and ME) is known for granite.  In fact, New Hampshire is nicknamed the "Granite State".  Granite is an igneous rock, formed by magma cooling underground.  Any organism trapped in magma likely would not leave a trace due to the extreme heat, so basically one can never find fossils in igneous rocks such as granite.

However, three of the Lake Champlain islands make up the Chazy Fossil Reef National Natural Landmark (Isle la Motte and Garden Island in VT, and Valcour Island in NY).  These islands have different rock compositions from their neighboring islands, being made up with limestone, and have preserved a great amount of fossils.  The fossils are from 450+ million years ago when the area was still under the sea level.  Gastropods (snails), cephalopods (octopi/squids), and other marine animals built the Chazy Reef, which is the oldest known diverse fossil reef in the world.

We visited the Goodsell Ridge Preserve and Fisk Quarry Preserve on Isle la Motte in hope to find some marine fossils.  We were not disappointed.  Goodsell Ridge has some "discovery zones" with bare limestone rocks, and we found a spot where multiple fossils were in close proximity from each other.  In contrast, Fisk Quarry was more of an open field; we found a couple gastropods, but took quite a bit more effort.


Extended reading:

(Vermont State Department of Environmental Conservation) Chazy Reef at Isle la Motte

(National Park Service) Chazy Fossil Reef











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