KT boundary Brazos 1 - A11.50 (Cretaceous of the United States)

Also known as Brazos River Section

Where: Texas (31.1° N, 96.8° W: paleocoordinates 34.5° N, 66.6° W)

• coordinate estimated from map

When: Corsicana Formation, Late/Upper Cretaceous (100.5 - 66.0 Ma)

Environment/lithology: marine; claystone

• Brazos-1 comprises approx. 1m of Cretaceous clay with dark clay clasts (up to 10 cm in diameter) at the base (Unit A) with evidence of physical disruption

•also see Figure 3 for the detailed section; Units B-E probably form a tempestite or tsunami

Size classes: macrofossils, mesofossils

Collection methods: bulk

Primary reference: T. Hansen, R. B. Farrand, H. A. Montgomery, H. G. Billman, and G. Blechschmidt. 1987. Sedimentology and extinction patterns across the Cretaceous-Tertiary boundary interval in East Texas. Cretaceous Research 8:229-252 [B. Seuss/B. Seuss]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 211326: authorized by Barbara Seuss, entered by Barbara Seuss on 14.07.2020

Creative Commons license: CC BY (attribution)

Taxonomic list

Coccolithophyceae
 Podorhabdales - Axopodorhabdaceae
 Braarudosphaerales - Polycyclolithaceae
Micula prinsii Perch-Nielsen 1979 coccolithophore
unclassified
  -
Foraminifera
  - Guembelitriidae
Guembelitria cretacea Cushman 1933
 Globigerinaceae - Heterohelicidae
Bivalvia
 Pectinida - Entoliidae
 Pectinida - Limidae
Lima sp. Bruguière 1797 file clam
 Ostreida - Flemingostreidae
"Ostrea falcata" = Agerostrea falcata, "Ostrea tecticosta" = Cubitostrea tecticosta
"Ostrea falcata" = Agerostrea falcata Morton 1827 oyster
"Ostrea tecticosta" = Cubitostrea tecticosta Gabb 1860 oyster
 Ostreida - Ostreidae
Ostrea "sp. A" Linnaeus 1758 oyster
Ostrea sp. Linnaeus 1758 oyster
 Arcida - Arcidae
 Carditida - Carditidae
 Lucinida - Lucinidae
Lucina sp., "Lucina linearia" = Nymphalucina linearia
Lucina sp. Bruguière 1797 clam
"Lucina linearia" = Nymphalucina linearia Stephenson 1941 clam
 Pandorida - Laternulidae
Anatimya sp. Conrad 1860 clam
 Cardiida - Mactridae
 Pholadida - Corbulidae
Corbula sp. Bruguière 1789 clam
 Nuculida - Nuculidae
Nucula "sp. A" Lamarck 1799 nut clam
 Nuculanida - Nuculanidae
Nuculana coloradoensis pointed nut clam
Nuculana travisana pointed nut clam
Nuculana "sp. A" Link 1807 pointed nut clam
Nuculana "sp. B" Link 1807 pointed nut clam
Nuculana sp. Link 1807 pointed nut clam
juveniles, adults
Nuculana "sp. E" Link 1807 pointed nut clam
Scaphopoda
 Gadilida - Gadilidae
Cadulus obnutus tusk shell
 Dentaliida - Dentaliidae
Dentalium "sp. B" Linnaeus 1758 tusk shell
Dentalium leve Stephenson 1923 tusk shell
Cephalopoda
 Ammonitida - Scaphitidae
Scaphites sp. Parkinson 1811 ammonite
 Ammonitida - Baculitidae
Baculites sp. Lamarck 1799 ammonite
Gastropoda
  -
Gastropoda indet. Cuvier 1795 snail
 Sorbeoconcha - Naticidae
Naticidae indet. Guilding 1834 moon snail
 Neogastropoda - Fasciolariidae
Fasciolariidae indet. Gray 1853 snail