The Verulam Formation is a geologic formation and Lagerstätte in Ontario, Canada. It preserves fossils dating back to the Katian stage of the Ordovician period, or Shermanian to Chatfieldian in the regional stratigraphy.Verulam Formation
Description The Verulam Formation belongs to the Simcoe Group in South-central Ontario and to the Trenton Group in Southwestern Ontario. Within the Simcoe Group, it overlies the Bobcaygeon Formation. Both the Bobcaygeon and Verulam Formations are composed of bioclastic wackestones, grainstones, and packstones interbedded with calcareous shales and siltstones. The Verulam contains more shale than the underlying Bobcaygeon Formation. Several hardgrounds have been documented in detail from the upper Bobcaygeon and lower Verulam. The paleoenvironments in which the Bobcaygeon and Verulam Formations were deposited have been interpreted as a proximal carbonate shelf that ranged in depth and proximity from shoal to shallow shelf in the Bobcaygeon and from deep shelf to shoal or shallow shelf in the Verulam Formation.Carden Quarry at Fossilworks.org
Fossil content The Verulam Formation and the underlying Bobcaygeon Formation have provided many fossils. Both formations form the Brechin Lagerstätte, a Lagerstätte of excellent preservation of numerous exceptionally preserved crinoid specimens with arms, stems, and attachment structures intact.Cole et al., 2018 Also ostracods, trilobites, bivalves, gastropods, cephalopods and other fossils were found in the formation.Waddington, 1980
Crinoids
Glyptocrinus ramulosus Isotomocrinus tenuis Cleiocrinus regius Priscillacrinus elegans Abludoglyptocrinus steinheimeraeCole et al., 2020 Pararchaeocrinus kiddi Periglyptocrinus astricus Periglyptocrinus kevinbretti Periglyptocrinus mcdonaldi Periglyptocrinus priscus Periglyptocrinus silvosus Cupulocrinus jewettiWright et al., 2019 Cupulocrinus humilis Praecupulocrinus conjugans Praecupulocrinus? sp. Iocrinus trentonensis Eustenocrinus springeri Cremacrinus guttenbergensis C. inaequalis Daedalocrinus bellevillensis Anomalocrinus astrictus Protaxocrinus laevis Plicodendrocrinus proboscidiatus Simcoecrinus mahalaki Dendrocrinus simcoensis Grenprisia billingsi Grenprisia springeri Illemocrinus amphiatus Porocrinus conicus Carabocrinus vancortlandti Carabocrinus radiatus Hybocrinus tumidus Hybocystites problematicus Konieckicrinus brechinensis K. josephi Reteocrinus alveolatus R. stellaris Archaeocrinus maraensis A. sundayae Trilobites Encrinurus cybeleformis Erratencrinurus vigilans Flexicalymene senaria Isotelus gigas Ceraurinus marginatus Ceraurus pleurexanthemus cf. Achatella achates Bathyurus (Raymondites) ingalli Amphilichas sp. Bumastoides sp. Calyptaulax sp. Ceraurus sp. Encrinuroides sp. Flexicalymene sp. Hemiarges sp. Isotelus sp. Edrioasteroidea Thresherodiscus ramosusSumrall & Gahn, 2006 Cryptogoleus chapmani Isorophusella sp. Ostracods Thomasatia sp. Bassleratia sp. Eoleperditia sp. Strophomenata Sowerbyella sp. Rafinesquina sp. Oepikina sp. Rhynchonellata Anazyga sp. Zygospira sp. Rhynchotrema sp. Resserella sp. Dinorthis sp. Hesperorthis sp. Platystrophia sp. Plectorthis sp. Bivalves Cyrtodonta subangulata Clionychia undata Plaesiomys subcircularisSproat & Jin, 2013 Ambonychia cf. orbicularis Ctenodonta cf. simulatrix Ambonychia sp. Ctenodonta sp. Nuculites sp. Tancrediopsis sp. Gastropods Bucania halli Hormotoma gracilis Sinuites cancellatus Eotomaria dryope Alaskadiscus disculus Cyrtostropha salteri canadensis Fusispira elongata F. angusta Pterotheca sp. Liospira sp. Lophospira sp. Hormotoma sp. Subulites sp. Fusispira sp. Cephalopods Endoceras cf. proteiforme Actinoceras sp. Endoceras sp. Stenolaemata Mesotrypa angularis M. quebecensis M. whiteavesi Homotrypa minnesotensis Prasopora grandis P. insularis P. simulatrix Eridotrypa aedilis Pachydictya sp. Stictoporella sp. Hallopora sp. Mesotrypa sp. Prasopora sp. Rhinidictya sp. Batostoma sp. Hallopora multitabulata Scyphozoa Climacoconus sp. Rhombifera Glyptocystites sp.
Chlorophyceae Ischadites sp.
See also List of fossiliferous stratigraphic units in Ontario Arnheim Formation, contemporaneous fossiliferous formation of Ohio San Benito Formation, contemporaneous fossiliferous formation of Bolivia Late Ordovician glaciation Ordovician meteor event Taconic orogeny
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