Cameron tracksite, MNA 789 (Triassic to of the United States)

Also known as Ward Terrace

Where: Coconino County, Arizona (35.9° N, 111.2° W: paleocoordinates 15.0° N, 50.5° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: Dinosaur Canyon Member (Moenave Formation), Rhaetian to Rhaetian (208.5 - 199.3 Ma)

• 40 m above base of member.

•Most of the Moenave Formation is the Dinosaur Canyon Member. In the Moenave type section, near Tuba City, Arizona, all of the Moenave section is Dinosaur Canyon Member, as it is throughout the Moenave outcrop belt along the Echo Cliffs and Ward's Terrace of northern Arizona. However, north of the Grand Canyon in Arizona and in southwestern Utah, the upper part of the Moenave Formation is lacustrine strata. These strata are the Whitmore Point Member.

•Lucas et al. (2011: Palaeo3 302: 194-205) proposed, on the basis of multiple lines of biostratigraphic evidence, that the Triassic–Jurassic boundary is placed within the middle part of the Whitmore Point Member of the Moenave Formation where this member is present, and high in the Dinosaur Canyon Member elsewhere. The "Whitmore Point assemblage" of vertebrate taxa, earliest Jurassic (Hettangian) in age. The underlying "Dinosaur Canyon assemblage", is latest Triassic (Rhaetian) in age.

•Because the stratigraphic position of this site within the Moenave is unclear, a Rhaetian–Hettangian age is given.

• bed-level stratigraphic resolution

Environment/lithology: interdune; bioturbated, brown, red, white, calcareous sandstone and bioturbated, brown, red, white, blue sandstone

• "deposited in shallow, slow-moving water...a damp, interdunal area (wadi)"
• "a light bluish-white to reddish-brown, very fine-grained, well sorted, calcareous sandstone...Sinuous-crested, water-laid ripples with a paleocurrent reading of 60 degrees (NE) occur in a 1.5x3.0 m area in the northeastern section of the track site...A high-angle, cross-bedded, light orangish to reddish-brown sandstone, measuring 7.2 m in thickness, underlies the bed. A mottled (bluish-white to reddish-brown), structureless, heavily bioturbated, very fine-grained sandstone overlies the track-bearing bed."

Size class: macrofossils

Preservation: mold/impression, trace

Collected by B. Brown, R. T. Bird in 1934

Collection methods: surface (in situ), peel or thin section,

• more than 300 tracks belonging to 34 trackways

Primary reference: S. K. Madsen. 1986. The rediscovery of dinosaur tracks near Cameron, Arizona. In D. D. Gillette (ed.), First International Symposium on Dinosaur Tracks and Traces, Abstracts with Program 20 [M. Carrano/M. Carrano]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 38886: authorized by Matthew Carrano, entered by Matthew Carrano on 13.05.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

 Saurischia -
Kayentapus sp. Welles 1971 theropod
 Saurischia - Eubrontidae
"Eubrontes sp." = Grallator (Eubrontes), "Grallator sp." = Grallator (Eubrontes), "Anchisauripus sp." = Grallator (Eubrontes)
"Eubrontes sp." = Grallator (Eubrontes) Hitchcock 1845 theropod
"Grallator sp." = Grallator (Eubrontes) Hitchcock 1845 theropod
"Anchisauripus sp." = Grallator (Eubrontes) Hitchcock 1845 theropod
 Saurischia - Grallatoridae
Dilophosauripus sp. Welles 1971 theropod