PBDB Collection

KT boundary Brazos 1 - A6.50 (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: deep subtidal shelf; claystone

• middle to outer shelf environment

• 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 225659: authorized by Barbara Seuss, entered by Barbara Seuss on 24.05.2022

Creative Commons license: CC BY (attribution)

Taxonomic list

Show authors, comments, and common names

unclassified
-	Heterohilicidae indet., Micula mura, Margaritella sp., Ammonoidea indet., Turborella sp., Cyclinchna incisa Heterohilicidae indet. Micula mura Margaritella sp. Ammonoidea indet. protoconchs Turborella sp. Cyclinchna incisa
Coccolithophyceae
Braarudosphaerales - Polycyclolithaceae	Micula prinsii Micula prinsii Perch-Nielsen 1979 coccolithophore
Podorhabdales - Axopodorhabdaceae	Nephrolithus frequens Nephrolithus frequens Górka 1957
Foraminifera
Globigerinaceae - Heterohelicidae	Heterohelix navarroensis, Heterohelix striata, Pseudoguembelina sp. Heterohelix navarroensis Loeblich 1951 Heterohelix striata Ehrenberg 1840 Pseudoguembelina sp.
- Guembelitriidae	Guembelitria cretacea Guembelitria cretacea Cushman 1933
Gastropoda
-	Gastropoda indet. Gastropoda indet. Cuvier 1795 snail
Heterostropha - Pyramidellidae	Creonella sp., Pyramidella sp. Creonella sp. Wade 1917 snail Pyramidella sp. Lamarck 1799 snail
Sorbeoconcha - Naticidae	Naticidae indet. Naticidae indet. Guilding 1834 moon snail
Neogastropoda -	Fulgerca attenuata Fulgerca attenuata Wade 1926 snail
Neogastropoda - Paladmetidae	Paladmete sp. Paladmete sp. Gardner 1916 snail
Neogastropoda - Fasciolariidae	Fasciolariidae indet. Fasciolariidae indet. Gray 1853 snail
Cerithioidea - Turritellidae	Turritella vertebrlides, Turritella sp., "Turritella bilira" = Haustator bilira Turritella vertebrlides turret shell Turritella sp. Lamarck 1799 turret shell "Turritella bilira" = Haustator bilira Stephenson 1941 turret shell
Bivalvia
-	Bivalvia indet. Bivalvia indet. Linnaeus 1758 clam
Nuculanida - Nuculanidae	Nuculana coloradoensis, Nuculana "sp. A", Nuculana "sp. B", Nuculana "sp. E", Nuculana longiformis, Nuculana protexa Nuculana coloradoensis pointed nut clam Nuculana "sp. A" Link 1807 pointed nut clam Nuculana "sp. B" Link 1807 pointed nut clam Nuculana "sp. E" Link 1807 pointed nut clam Nuculana longiformis pointed nut clam Nuculana protexa pointed nut clam
Solemyida - Solemyidae	Solemya sp. Solemya sp. Children 1823 Awning Clam
Nuculida - Nuculidae	Nucula "sp. A" Nucula "sp. A" Lamarck 1799 nut clam
Poromyida - Cuspidariidae	Cuspidaria sp., Cuspidaria grandis Cuspidaria sp. Dall 1886 clam Cuspidaria grandis Stephenson 1941 clam
Thraciida - Periplomatidae	Periploma sp. Periploma sp. Schumacher 1816 clam
Pholadida - Corbulidae	"Corbula texana" = Notocorbula texana "Corbula texana" = Notocorbula texana Gabb 1860 clam Corbula subradiata texana
Cardiida - Mactridae	Cymbophora cancellosa Cymbophora cancellosa clam
Cardiida - Cardiidae	Trachycardium sp. Trachycardium sp. Mörch 1853 cockle
Carditida - Crassatellidae	Crassatella sp. Crassatella sp. Lamarck 1799 clam
Arcida - Arcidae	Striarca webbervillensis Striarca webbervillensis clam
Arcida - Parallelodontidae	Nemodon lineatus Nemodon lineatus clam Nemodon eufalensis lineatus
Pectinida - Entoliidae	Syncyclonema simplicus, Syncyclonema travisana Syncyclonema simplicus scallop Syncyclonema travisana scallop
Pectinida - Limidae	Lima sp. Lima sp. Bruguière 1797 file clam
Pectinida - Anomiidae	Anomia sp., Anomia argentaria Anomia sp. Linnaeus 1758 jingle Anomia argentaria Morton 1833 jingle
Ostreida - Ostreidae	Ostrea "sp. A" Ostrea "sp. A" Linnaeus 1758 oyster
Ostreida - Flemingostreidae	"Ostrea falcata" = Agerostrea falcata, "Ostrea tecticosta" = Cubitostrea tecticosta "Ostrea falcata" = Agerostrea falcata Morton 1827 oyster "Ostrea tecticosta" = Cubitostrea tecticosta Gabb 1860 oyster
Scaphopoda
Dentaliida - Dentaliidae	Dentalium "sp. B", Dentalium leve Dentalium "sp. B" Linnaeus 1758 tusk shell Dentalium leve Stephenson 1923 tusk shell
Gadilida - Gadilidae	Cadulus obnutus Cadulus obnutus tusk shell
Cephalopoda
Ammonitida - Scaphitidae	Scaphites sp. Scaphites sp. Parkinson 1811 ammonite
Ammonitida - Baculitidae	Baculites sp. Baculites sp. Lamarck 1799 ammonite