Chazy Fossil Reef is a United States

National Natural Landmark The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best ...

spanning three

Lake Champlain Lake Champlain ( ; french: Lac Champlain) is a natural freshwater lake in North America. It mostly lies between the US states of New York and Vermont, but also extends north into the Canada, Canadian province of Quebec. The New York portion of t ...

islands in

Clinton County Clinton County may refer to: *Counties named for George Clinton, first and third Governor of New York, and later the fourth Vice President of the United States: **Clinton County, New York ** Clinton County, Ohio *Counties named for DeWitt Clinton, ...

, New York and Grand Isle County,

Vermont Vermont () is a state in the northeast New England region of the United States. Vermont is bordered by the states of Massachusetts to the south, New Hampshire to the east, and New York to the west, and the Canadian province of Quebec to ...

. The site is recognized as the oldest known diverse

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...

in the world, and contains fossils that demonstrate

faunal succession The principle of faunal succession, also known as the law of faunal succession, is based on the observation that sedimentary rock strata contain fossilized flora and fauna, and that these fossils succeed each other vertically in a specific, reli ...

. The site was dedicated as a National Natural Landmark in May 2009.

Location

The Chazy Fossil Reef National Natural Landmark includes three islands in

. Included within the designated area are two preserves on Vermont's

Isle La Motte Isle La Motte is an island in Lake Champlain in northwestern Vermont, United States. At 7 mi (11 km) by 2 mi (3 km), it lies close to the place that the lake empties into the Richelieu River. It is incorporated as a New England town in Grand Isle ...

; the Fisk Quarry Preserve and the Goodsell Ridge Preserve are both open to the public and managed by the Isle La Motte Preservation Trust. New York's Valcour Island and Garden Island are also included as part of the landmark.

Fossils

The reef is an observable portion of the larger

Chazy Formation The Chazy Reef Formation is a mid-Ordovician limestone deposit in northeastern North America. It consists of some of the oldest reef systems built by a community of organisms rather than the deposit of a limited range of similar organisms, such ...

which extends from

Quebec Quebec ( ; )According to the Canadian government, ''Québec'' (with the acute accent) is the official name in Canadian French and ''Quebec'' (without the accent) is the province's official name in Canadian English is one of the thirtee ...

Tennessee Tennessee ( , ), officially the State of Tennessee, is a landlocked state in the Southeastern region of the United States. Tennessee is the 36th-largest by area and the 15th-most populous of the 50 states. It is bordered by Kentucky to th ...

. The location features an exposed

Ordovician The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. T ...

fossil reef, approximately 450 to 480 million years old, containing fossils from what was once a tropical marine environment. The site is recognized as the oldest known fossil reef that contains substantial

biological diversity Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic ('' genetic variability''), species ('' species diversity''), and ecosystem ('' ecosystem diversity'') ...

. Strata from successive periods of time may be viewed across the landscape due to the tilted orientation of the sedimentary rock layers. The presence of fossils from a continuous time series allow for the observation of

. On Isle La Motte, the oldest fossils occur at the southern end of the island, with progressively newer layers visible toward the island's north end. Among the preserved specimens are prehistoric stromatoporoids, gastropods, cephalopods,

echinoderm An echinoderm () is any member of the phylum Echinodermata (). The adults are recognisable by their (usually five-point) radial symmetry, and include starfish, brittle stars, sea urchins, sand dollars, and sea cucumbers, as well as the s ...

brachiopod Brachiopods (), phylum Brachiopoda, are a phylum of trochozoan animals that have hard "valves" (shells) on the upper and lower surfaces, unlike the left and right arrangement in bivalve molluscs. Brachiopod valves are hinged at the rear end, w ...

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...

coral Corals are marine invertebrates within the class Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and ...

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a ...

and

stromatolites Stromatolites () or stromatoliths () are layered sedimentary formations (microbialite) that are created mainly by photosynthetic microorganisms such as cyanobacteria, sulfate-reducing bacteria, and Pseudomonadota (formerly proteobacteria). Th ...

References

{{authority control National Natural Landmarks in New York (state) National Natural Landmarks in Vermont Ordovician geology of New York (state) Ordovician geology of Vermont Lake Champlain

Location

Fossils

See also

References