McCoy Brook Formation
Geological formation in Nova Scotia
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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: | |
Breccia in the McCoy Brook Formation (Jurassic), Wasson's Bluff, Nova Scotia. | |
| Type | Geological formation |
| Unit of | Newark Supergroup Meriden Group |
| Sub-units | Scots Bay Member |
| Underlies | Erosional top |
| Overlies | North Mountain Basalt |
| Thickness | more than 230 m (750 ft) |
| Location | |
| Coordinates | 45.4°N 64.2°W |
| Approximate paleocoordinates | 27.4°N 13.3°W |
| Region | Nova Scotia |
| Country | Canada |
| Extent | Bay of Fundy |
| Type section | |
| Named for | McCoy Brook, Nova Scotia |
  McCoy Brook Formation (Canada)  McCoy Brook Formation (Nova Scotia) | |
Agen
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
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
Sharks
Color key
|
Notes Uncertain or tentative taxa are in small text; |
Ray-finned fish
| Ray-finned fish | ||||||
|---|---|---|---|---|---|---|
| Name | Species | Location | Stratigraphic position | Material | Notes | Images |
|
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 |
 |
Synapsids
| Synapsids | ||||||
|---|---|---|---|---|---|---|
| Name | Species | Location | Stratigraphic position | Material | Notes | Images |
|
Indeterminate |
Wasson Bluff |
Scots Bay Member |
|
A cynodont | ||
|
Oligokyphus sp. |
Wasson Bluff |
Scots Bay Member |
Fragment of a right Dentary. |
A tritheledontid cynodont, found in the layers of the Scots Bay member. |
 | |
|
cf. P. monus |
Wasson Bluff |
Upper Member |
Excellently preserved fragments of two premaxillae, ten maxillae, and six dentaries |
 | ||
|
Indeterminate |
Wasson Bluff |
Scots Bay Member |
Right humerus |
A tritylodontid cynodont, found in the layers of the Scots Bay member. |
||
Sphenodonts
| Sphenodonts | ||||||
|---|---|---|---|---|---|---|
| Name | Species | Location | Stratigraphic position | Material | Notes | Images |
|
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 |
 | |
|
Indeterminate |
Wasson Bluff |
Middle McCoy Brook Formation |
Isolated Remains |
|||
|
Indeterminate |
Wasson Bluff |
Middle McCoy Brook Formation |
Isolated Remains |
|||
Crocodyliforms
| 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] |
 |
|
Indeterminate |
|
Lower McCoy Brook Formation |
|
Found in fluvio-lacustrine sandstone and mudstone, and basalt agglomerate |
||
Dinosaurs
Ornithischia
| Ornithischians | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | |
|
Indeterminate |
Wasson Bluff |
Scots Bay Member |
|
Suggested to be similar to Scutellosaurus and to Leshotosaurus. Represent among the oldest reliable Ornithischian remains of North America. | ||
Theropoda
| Ornithischians | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | |
|
Indeterminate |
Wasson Bluff |
Scots Bay Member |
Teeth |
Theropod dinosaur teeth similar to Megapnosaurus. | ||
Sauropodomorpha
| Sauropodomorph dinosaurs | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
|
F. eldoni |
Wasson Bluff |
Middle McCoy Brook Formation |
|
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
Color key
|
Notes Uncertain or tentative taxa are in small text; |
| Ichnotaxa | ||||||
|---|---|---|---|---|---|---|
| Genus | Species | Location | Stratigraphic position | Material | Notes | Images |
|
|
Middle McCoy Brook Formation |
Footprints |
Small Theropod Footprints |
||
|
|
Middle McCoy Brook Formation |
Footprints |
Ornithischian Footprints |
||
|
|
Middle McCoy Brook Formation |
Footprints |
Crocodrylomorph Footprints |
||
|
|
Middle McCoy Brook Formation |
Footprints |
Medium-sized Theropod Footprints |
||
|
|
Middle McCoy Brook Formation |
Footprints |
Small Theropod Footprints |
 | |
|
|
Middle McCoy Brook Formation |
Footprints |
Sauropodomorph Footprints |
 | |