| Becscie Formation | |
|---|---|
| Stratigraphic range: | |
| Type | Geological formation |
| Sub-units |
|
| Underlies | Gun River Formation |
| Overlies | Ellis Bay Formation |
| Thickness | 80 to 85 meters |
| Location | |
| Region |  Quebec |
| Country |  Canada |
The Becscie Formation is a geologic formation in Quebec. It preserves fossils dating back to the early Silurian period.
The Becscie Formation is 80 to 85 meters thick. [1] It overlies the Ordovician-Silurian boundary on Anticosti Island, marking a major oceanic and climatic changeover from the glacial sea-level lowstand and interglacial highstand cycles of the underlying Ellis Bay Formation to the more stable warming climate of the earliest Silurian, and extends approximately parallel to an ancient coastline some 200 km east to west. [1] The formation is divided into two members, a lower Fox Point Member (spanning the Viridita lenticularis Biozone), and an upper Chabot Member (spanning the Virgiana barrandei Biozone). [1]
| Arthropods | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Anticostibolbina | Chabot Member. [1] | A beyrichiacean ostracod. | |||
| Bolbineossia | Chabot Member. [1] | A beyrichiacean ostracod. | |||
| Conbathella | Chabot Member. [1] | A beyrichiacean ostracod. | |||
| Herrmannina | H. selwyni | Lower Becscie Formation. [1] | An ostracod | ||
| Zygobursa | Chabot Member. [1] | A beyrichiacean ostracod. | |||
| Brachiopods | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Becscia | B. scissura | "Occurs commonly in lenses and clusters". [1] | An atrypid. [1] | ||
| Biparetis | Elsewhere known from the early Silurian, but locally rare. [1] | ||||
| Brachyprion | Occurs sparsely in the Chabot Member. [1] | ||||
| Eospirigerina | E. sp. | Fox Point Member. [1] | An unnamed species, represents earliest known Silurian species of this Ordovician genus. | ||
| Hesperorthis | Fox Point Member. [1] | An orthide. [1] | |||
| Isorthis (Ovalella) | Fox Point Member. [1] | An orthide. [1] | |||
| Koigia | An athyridid, originally reported as Hindella. [1] | ||||
| Leptaena | Fox Point Member bedding plane. [1] | ||||
| Mendacella | M. udauberis | Fox Point Member, rare in the Chabot Member. [1] | An orthide. [1] | ||
| Saukrodictya | Fox Point Member. [1] | An orthide. [1] | |||
| Virgiana | V. barrandei | Only in the Chabot Member. [1] [2] | A large-shelled pentameride. [1] | ||
| Viridita | V. becsciensis | Fox Point Member. [2] | "Holotype, YPM 10341, and paratype, YPM 35519". [2] | ||
| V. lenticularis | Near the top of the Fox Point Member, [1] and the Chabot Member. [2] | ||||
| Zygospiraella | Z. cf. Z. planoconvexa | Lower Becscie Formation, rare taxon in the lower Chabot Member. [1] | |||
| Bryozoans | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Phaenopora | P. superba | Fox Point and Chabot Members. [1] | "Extends into the overlying Gun River Formation" [3] | ||
| Corals | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Acidolites | A. arctatus | [4] | A heliolitid. | ||
| A. compactus | [4] | A heliolitid. | |||
| A. lindströmi | [4] | A heliolitid. | |||
| Nanonphyllum | N. pelagicum | Common in the Chabot Member. [1] | A colonial rugose coral. | ||
| Paleofavosites | More common towards the upper part of the Fox Point Member. [1] | A heliolitid tabulate coral. [1] | |||
| Palaeophyllum | Common in the Chabot Member. [1] | ||||
| Propora | More common towards the upper part of the Fox Point Member. [1] | A heliolitid tabulate coral. [1] | |||
| Crinoids | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Alopocrinus | Fox Point and Chabot members. [1] | ||||
| Becsciecrinus | Fox Point and Chabot members. [1] | ||||
| Dendrocrinus | Chabot Member. [1] | ||||
| Eumyelodactylus | Fox Point Member. [1] | ||||
| Euspirocrinus | Fox Point Member. [1] | ||||
| Protaxocrinus | Fox Point Member. [1] | ||||
| Xenocrinus | Chabot Member. [1] | ||||
| Gastropods | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Hormotoma | Eastern side of Anticosti Island. [1] | A hormotomid. | |||
| Subulites | Eastern side of Anticosti Island. [1] | A soleniscid. | |||
| Graptolites | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Climacograptus | C. typicalis var. atlanticus | [5] | |||
| Sponges | |||||
|---|---|---|---|---|---|
| Genus | Species | Presence | Material | Notes | Images |
| Clathrodictyon | C. boreale | Fox Point and Chabot members. [1] | "A single small, spheroidal specimen". [1] | A stromatoporoid. [1] | |
| Ecclimadictyon | E. macrotuberculatum | Chabot Member. [1] | A stromatoporoid. | ||
| Pachystylostroma | Very top of the Chabot Member. [1] | A stromatoporoid. | |||
The Silurian is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago (Mya), to the beginning of the Devonian Period, 419.2 Mya. The Silurian is the shortest period of the Paleozoic Era. As with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by a few million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when up to 60% of marine genera were wiped out.
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Paleontology in Oklahoma refers to paleontological research occurring within or conducted by people from the U.S. state of Oklahoma. Oklahoma has a rich fossil record spanning all three eras of the Phanerozoic Eon. Oklahoma is the best source of Pennsylvanian fossils in the United States due to having an exceptionally complete geologic record of the epoch. From the Cambrian to the Devonian, all of Oklahoma was covered by a sea that would come to be home to creatures like brachiopods, bryozoans, graptolites and trilobites. During the Carboniferous, an expanse of coastal deltaic swamps formed in areas of the state where early tetrapods would leave behind footprints that would later fossilize. The sea withdrew altogether during the Permian period. Oklahoma was home a variety of insects as well as early amphibians and reptiles. Oklahoma stayed dry for most of the Mesozoic. During the Late Triassic, carnivorous dinosaurs left behind footprints that would later fossilize. During the Cretaceous, however, the state was mostly covered by the Western Interior Seaway, which was home to huge ammonites and other marine invertebrates. During the Cenozoic, Oklahoma became home to creatures like bison, camels, creodonts, and horses. During the Ice Age, the state was home to mammoths and mastodons. Local Native Americans are known to have used fossils for medicinal purposes. The Jurassic dinosaur Saurophaganax maximus is the Oklahoma state fossil.
The Georgian Bay Formation is a geologic formation in Michigan and Ontario. It preserves fossils dating back to the Ordovician period. The type locality of the formation is on East Meaford Creek, south shore of Nottawasaga Bay, Georgian Bay.
The Johnson Spring Formation is a geologic formation in California. It preserves fossils dating back to the Ordovician period.
The Attawapiskat Formation is a geologic formation in Ontario. It preserves fossils dating back to the Silurian period.
The Merrimack Formation is a geologic formation in Quebec. It preserves fossils dating back to the Silurian period.
The Gun River Formation is a geologic formation in Quebec. It preserves fossils dating back to the early Silurian period.
The Jupiter Formation is a geologic formation in Quebec, well-exposed in the southern third of Anticosti Island and lying in the St Lawrence River Valley. It preserves fossils dating back to the Silurian period.
The Campbellton Formation is a geologic formation in New Brunswick. It preserves fossils dating back to the latest Pragian and Emsian of the Devonian period.
The Solvik Formation is a geologic formation in the central Oslo Region of Norway. It preserves fossils dating back to the early Silurian period.
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