Gwynedd Tunnel (track layers) (Triassic of the United States)

Where: Montgomery County, Pennsylvania (40.2° N, 75.3° W: paleocoordinates 14.7° N, 20.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Lockatong Formation (Chatham Group), Norian (228.0 - 208.5 Ma)

• group of beds-level stratigraphic resolution

Environment/lithology: "floodplain"; gray, blue claystone

• "the final phase of a flood deposit"
• "a bluish-gray argillite, weathering brown", also described as a "hard grayish shale" and "heavy bedded gray shale, which is hard and will rarely split...The surface of these heavy layers often bears mud-cracks and ripple marks"

Size class: macrofossils

Preservation: mold/impression, trace

Collection methods: quarrying, surface (float), surface (in situ),

Primary reference: W. L. Bryant. 1934. New fishes from the Triassic of Pennsylvania. Proceedings of the American Philosophical Society 73(5):319-326 [M. Carrano/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 68706: authorized by Matthew Carrano, entered by Matthew Carrano on 02.02.2007

Creative Commons license: CC BY (attribution)

Taxonomic list

Reptilia
 Pseudosuchia - Gwyneddichniidae
Gwyneddichnium majore n. gen. n. sp. Bock 1952 archosaur
Gwyneddichnium elongatum n. sp. Bock 1952 archosaur
Gwyneddichnium minore n. sp. Bock 1952 archosaur
 Theropoda - Grallatoridae
Anchisauripus gwyneddensis n. sp. Bock 1952 theropod
 Saurischia -
Platypterna lockatong n. sp. Bock 1952 saurischian
  -
Kintneria brunswickii Ryan and Willard 1947 reptile