TMM 43621-1, North Grapevine Hills (170 m) (Cretaceous of the United States)

Also known as Big Bend N.P.

Where: Brewster County, Texas (29.4° N, 103.2° W: paleocoordinates 36.0° N, 82.5° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Black Peaks Formation (Tornillo Group), Late/Upper Maastrichtian (70.6 - 66.0 Ma)

• Just below the Cretaceous/Tertiary boundary and approx. 50 m above the Javelina Formation; located about 90 meters above a tuff dated as 69.0 ± 0.9 Ma (U-Pb) (late Edmontonian to Lancian NALMA)

• bed-level stratigraphic resolution

Environment/lithology: lacustrine - small; burrowed, gray, calcareous mudstone and limestone

• Deposited in a flood-plain pond or shallow lake
• Dark olive-gray calcareous mudstone layer several decimeters below the thin-limestone bed. Large cylindrical smooth-walled burrows, filled with pelloidal microcrystalline calcite, descend from the limstone layer and penetrate through the underlying mudstone , surrounding the bones and ramifying beneath the bone bone-bearing horizon.

Size class: macrofossils

Preservation: replaced with calcite

Collected by T. Lehman in 1995; reposited in the TMM

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

Primary reference: T. M. Lehman and A. B. Coulson. 2002. A juvenile specimen of the sauropod dinosaur Alamosaurus sanjuanensis from the Upper Cretaceous of Big Bend National Park, Texas. Journal of Paleontology 76(1):156-172 [M. Carrano/K. Maguire/M. Carrano]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 52087: authorized by Matthew Carrano, entered by Kaitlin Maguire on 20.07.2005, edited by Matthew Carrano

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names
Reptilia
 Saurischia - Saltasauridae
Alamosaurus sanjuanensis
Alamosaurus sanjuanensis Gilmore 1922 saltasaurine
TMM 43621-1 (field no. TL 95-1)
unclassified
  -
Charophyta indet.
Charophyta indet. Migula 1890