Wikipedia

McCoy Brook Formation

The McCoy Brook Formation is a geological formation dating to roughly between 200 and 190 million years ago and covering the Hettangian to Sinemurian stages. The McCoy Brook Formation is found in outcrops around the Bay of Fundy, Nova Scotia.[1]

McCoy Brook Formation
Stratigraphic range: Hettangian–Sinemurian
Breccia in the McCoy Brook Formation (Jurassic), Wasson's Bluff, Nova Scotia.
TypeGeological formation
Unit ofNewark Supergroup
 Meriden Group
Sub-unitsScots Bay Member
UnderliesErosional top
OverliesNorth Mountain Basalt
Thicknessmore than 230 m (750 ft)
Location
Coordinates45°24′N 64°12′W / 45.4°N 64.2°W / 45.4; -64.2
Approximate paleocoordinates27°24′N 13°18′W / 27.4°N 13.3°W / 27.4; -13.3
Region Nova Scotia
Country Canada
ExtentBay of Fundy
Type section
Named forMcCoy Brook, Nova Scotia
McCoy Brook Formation is located in Canada
McCoy Brook Formation
McCoy Brook Formation (Canada)
McCoy Brook Formation is located in Nova Scotia
McCoy Brook Formation
McCoy Brook Formation (Nova Scotia)

Agen

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The McCoy Brook Formation rests on the North Mountain Basalt, one of the volcanic flows associated with the Triassic–Jurassic boundary in the Newark Supergroup. The base of the McCoy Brook Formation is probably within 100,000 to 200,000 years of the boundary.[2]

Scots Bay Member

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This thin unit (9 m) of lacustrine sediments is preserved in six small synclinal outcrops around Scots Bay on the west side of the Blomidon Peninsula. Originally named as the Scots Bay Formation, it is now correlated with the lowermost part of the McCoy Brook Formation, where it is referred to as the Scots Bay Member.[3][4] The Scots Bay Member accumulated in an aerobic lake on the floor of the subtropical Fundy Rift Valley, associated with Silica-rich Hydrothermal Springs derived from the CAMP vulcanism, where the biota is composed of algal Stromatolites, Oncolites, Charophyta, Ostracoda, Gastropoda, Conchostraca, fish bones, calcispheres and logs.[5]

Fossil content

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Sharks

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Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Sharks
Name Species Location Stratigraphic position Material Notes

cf.Hybodus[2][6]

Indeterminate

Wasson Bluff

Scots Bay member

Teeth & Coprolites

A hybodont shark. Recovered from lacustrine facies

 
Two Hybodus

Ray-finned fish

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Ray-finned fish
Name Species Location Stratigraphic position Material Notes Images

?Redfieldiid[2][7]

None designated

Wasson Bluff

Scots Bay member

Scales and skull bones[2]

Found in lacustrine limestone and lacustrine basalt aggregate

aff. Semionotus sp.[2][7]

None designated

Wasson Bluff

Scots Bay member

Disarticulated remains

Found in lacustrine limestone, lacustrine basalt aggregate, and lacustrine mudstone

 
Semionotus

Synapsids

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Synapsids
Name Species Location Stratigraphic position Material Notes Images

Cynodontia[7][8]

Indeterminate

Wasson Bluff

Scots Bay Member

  • Partial right unla
  • Proximal portion of a right ischium

A cynodont

Oligokyphus[7][8]

Oligokyphus sp.

Wasson Bluff

Scots Bay Member

Fragment of a right Dentary.

A tritheledontid cynodont, found in the layers of the Scots Bay member.

 
Oligokyphus

Pachygenelus[7][9]

cf. P. monus

Wasson Bluff

Upper Member

Excellently preserved fragments of two premaxillae, ten maxillae, and six dentaries

A tritheledontid cynodont

 
Pachygenelus

Tritylodontidae[7][8]

Indeterminate

Wasson Bluff

Scots Bay Member

Right humerus

A tritylodontid cynodont, found in the layers of the Scots Bay member.

Sphenodonts

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Sphenodonts
Name Species Location Stratigraphic position Material Notes Images

Clevosaurus[10]

C. bairdi[10]

Wasson Bluff

Lower McCoy Brook Formation

Partial skulls and jaws, isolated cranial bones, partial postcranium, postcranial bones

A sphenodontian of relatively small size,[10] found in fluvio-lacustrine sandstone and mudstone, and basalt agglomerate

 
Clevosaurus

cf. Palycymalia[6][7]

Indeterminate

Wasson Bluff

Middle McCoy Brook Formation

Isolated Remains

A sphenodontian

cf. Sigmala[6][7]

Indeterminate

Wasson Bluff

Middle McCoy Brook Formation

Isolated Remains

A sphenodontian

Crocodyliforms

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Protosuchidae
Genus Species Location Stratigraphic position Material Notes Images
Protosuchus[6][11]

P. micmac[11]

Wasson Bluff

Lower McCoy Brook Formation

Partial lower jaw, several other skull bones[11]

Found in fluvio-lacustrine sandstone and mudstone, and basalt agglomerate[2]

 
Protosuchus

Sphenosuchid[2][6]

Indeterminate

  • Blue sack west
  • Wasson Bluff

Lower McCoy Brook Formation

Found in fluvio-lacustrine sandstone and mudstone, and basalt agglomerate

Dinosaurs

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Ornithischia

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Ornithischians
Genus Species Location Stratigraphic position Material Notes

Ornithischia[2][7][6]

Indeterminate

Wasson Bluff

Scots Bay Member

  • Impressions of teeth (YPM VP 008668, VP 008691)
  • Vertebral centra (YPM VP 008693)
  • Possible rib fragments (YPM VP008694, VP 008695)

Suggested to be similar to Scutellosaurus and to Leshotosaurus. Represent among the oldest reliable Ornithischian remains of North America.

Theropoda

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Ornithischians
Genus Species Location Stratigraphic position Material Notes

Theropoda[1][6]

Indeterminate

Wasson Bluff

Scots Bay Member

Teeth

Theropod dinosaur teeth similar to Megapnosaurus.

Sauropodomorpha

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Sauropodomorph dinosaurs
Genus Species Location Stratigraphic position Material Notes Images

Fendusaurus[12]

F. eldoni

Wasson Bluff

Middle McCoy Brook Formation

  • YPM VPPU 022196, several vertebrae and limb-bone fragments
  • FGM994GF69, postcranial skeleton
  • FGM998GF9, partial skeleton
  • FGM998GF13_I, large, articulated specimen
  • FGM998GF13/FGM998GF13_III postcranea and dissociated skull
  • NSM005GF009/FGM998GF46, partial, badly deformed and fragmentary skeleton with gastroliths

Although long assigned to Ammosaurus, the material actually represents a new genus and species; represents the most abundant dinosaur in the formation, and has yield specimens with preserved stomach contents that suggest migration patterns. The possibility that represents more than one genus is open.[6]

Ichnotaxa

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Color key
Taxon Reclassified taxon Taxon falsely reported as present Dubious taxon or junior synonym Ichnotaxon Ootaxon Morphotaxon
Notes
Uncertain or tentative taxa are in small text; crossed out taxa are discredited.
Ichnotaxa
Genus Species Location Stratigraphic position Material Notes Images

Anchisauripus[6]

  • A. sillimani
  • A. ispp.
  • Blue sack west
  • McKay Head
  • Wasson Bluff

Middle McCoy Brook Formation

Footprints

Small Theropod Footprints

Anomoepus[2][6]

  • A. scambus
  • A. ispp.
  • Blue sack west
  • McKay Head
  • Old Wife Point tracksite

Middle McCoy Brook Formation

Footprints

Ornithischian Footprints

Batrachopus[6][13]

  • B. deweyii
  • B. dispar
  • B. ispp.
  • McKay Head
  • Old Wife Point tracksite
  • Wasson Bluff tracksite

Middle McCoy Brook Formation

Footprints

Crocodrylomorph Footprints

Eubrontes[6][13]

  • E. giganteus
  • E. sillimani
  • E. minusculus
  • E ispp.
  • Five Islands Provincial Park
  • Old Wife Point tracksite
  • Wasson Bluff tracksite

Middle McCoy Brook Formation

Footprints

Medium-sized Theropod Footprints

Grallator[2][6]

  • G. cursorius
  • G. tenuis
  • G. ispp.
  • McKay Head
  • Old Wife Point tracksite

Middle McCoy Brook Formation

Footprints

Small Theropod Footprints

 
Grallator

Otozoum[6][2][14]

  • O. moodi
  • O. ispp.
  • Blue sack east
  • McKay Head
  • Minas Basin tracksite

Middle McCoy Brook Formation

Footprints

Sauropodomorph Footprints

 
Otozoum

See also

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References

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  1. ^ a b Van Drecht, L. (2014). "Sedimentology and Paleoenvironment of an Early Jurassic Dinosaur Bone Bed, Wasson Bluff, Parrsboro, Nova Scotia" (PDF). Submitted in Partial Fulfillment of the Requirements for the Degree of Bachelor of Sciences, Honours Department of Earth Sciences Dalhousie University, Halifax: 1–80. Retrieved 11 October 2023.
  2. ^ a b c d e f g h i j k Shubin, N. H.; Olsen, P. E.; Sues, H.-D. (1994). "Early Jurassic small tetrapods from the McCoy Brook Formation of Nova Scotia, Canada". In Fraser, N. C.; Sues H. D. (eds.). In the Shadow of the Dinosaurs. Cambridge, United Kingdom: Cambridge University Press. pp. 242–250. ISBN 0-521-45899-4.
  3. ^ Tanner, L.H. (1996). "Formal definition of the Lower Jurassic McCoy Brook Formation, Fundy Rift Basin, eastern Canada". Atlantic Geology. 32 (2): 127–135. doi:10.4138/2083. Retrieved 15 December 2012.
  4. ^ Hassan, H.S. "Sedimentology and Paleontology of the Lower Jurassic Scots Bay Formation, Bay of Fundy, Nova Scotia, Canada" (PDF). MSc thesis. Retrieved 24 November 2012.
  5. ^ De WET, C. C. B.; Hubert, J. F. (1989). "The Scots Bay formation, Nova Scotia, Canada, a Jurassic carbonate lake with Silica-rich hydrothermal springs". Sedimentology. 36 (5): 857–873. Bibcode:1989Sedim..36..857W. doi:10.1111/j.1365-3091.1989.tb01750.x. Retrieved 11 October 2023.
  6. ^ a b c d e f g h i j k l m n Sues, H. D.; Olsen, P. E. (2015). "Stratigraphic and temporal context and faunal diversity of Permian-Jurassic continental tetrapod assemblages from the Fundy rift basin, eastern Canada". Atlantic Geology. 51 (1): 139–205. doi:10.4138/atlgeol.2015.006. Retrieved 11 October 2023.
  7. ^ a b c d e f g h i Olsen, P. E. (1988). "Paleontology and paleoecology of the Newark Supergroup (early Mesozoic, eastern North America)". Developments in Geotectonics. 22 (1): 185–230. doi:10.1016/B978-0-444-42903-2.50013-0. ISBN 978-0-444-42903-2. Retrieved 11 October 2023.
  8. ^ a b c Fedak, Tim; Sues, Hans-Dieter; Olsen, Paul E. (2015). "First record of the tritylodontid cynodont Oligokyphus and cynodont postcranial bones from the McCoy Brook Formation of Nova Scotia, Canada". Canadian Journal of Earth Sciences. 52 (4): 244–249. Bibcode:2015CaJES..52..244F. doi:10.1139/cjes-2014-0220. Retrieved 11 October 2023.
  9. ^ Shubin, N. H.; Crompton, A. W.; Sues, H.D.; Olsen, P. E. (1991). "New fossil evidence on the sister-group of mammals and early Mesozoic faunal distributions". Science. 251 (4997): 1063–1065. Bibcode:1991Sci...251.1063S. doi:10.1126/science.251.4997.1063. PMID 17802092. Retrieved 11 October 2023.
  10. ^ a b c Sues, H.-D.; Shubin, N. H.; Olsen, P. E. (1994). "A new sphenodontian (Lepidosauria: Rhynchocephalia) from the McCoy Brook Formation (Lower Jurassic) of Nova Scotia, Canada". Journal of Vertebrate Paleontology. 14 (3): 327–340. Bibcode:1994JVPal..14..327S. doi:10.1080/02724634.1994.10011563.
  11. ^ a b c Sues, H.-D.; Shubin, N. H.; Olsen, P. E.; Amaral, W. W. (1996). "On the cranial structure of a new protosuchid (Archosauria: Crocodyliformes) from the McCoy Brook Formation (Lower Jurassic) of Nova Scotia, Canada". Journal of Vertebrate Paleontology. 16 (1): 34–41. Bibcode:1996JVPal..16...34S. doi:10.1080/02724634.1996.10011281.
  12. ^ Fedak, Timothy J. (2007). "Description and evolutionary significance of the sauropodomorph dinosaurs from the early Jurassic (Hettangian) McCoy Brook Formation". Thesis (Ph.D.)--Dalhousie University (Canada) (1–271). Retrieved 11 October 2023.
  13. ^ a b Olsen, P. E. (1989). "Stop 11.3: Wasson Bluff. Paleontology". Tectonic, Depositional, and Paleoecological History of Early Mesozoic Rift Basins, Eastern North America. 351 (2): 159–161.
  14. ^ Grantham, R. G. (1986). "Dinosaur tracks and mega-flutes in the Jurassic of Nova Scotia". First International Symposium on Dinosaur Tracks and Traces. 14.
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