Langley Core, VA - 8.41-8.47 m (Yorktown Fm) (Pliocene of the United States)

Also known as 27.6-27.8 ft

Where: Hampton County, Virginia (37.1° N, 76.4° W: paleocoordinates 37.1° N, 75.7° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Yorktown Formation, Late/Upper Pliocene (3.6 - 2.6 Ma)

• SOURCE: collecton from 8.41-8.47 m (27.6-27.8 ft) in core. STRATIGRAPHIC RELATIONS: Overlies unconformably with a heavy burrowed contact, the Late Miocene Eastover Fm as 23.3 m (76.3 ft). The Yorktown is further overlain by 2.2. m (7.2 ft of Quaternary gravel and sand of the Lynn Haven Mr of the Tabb Fm. The Chown River and Bacons Castles Fm's are not recognized in the core. BIOSTRATIGRAPHY: NN 14-17 calcareous nannofossil zone and M5-M6 molluscan zone = Early-Late Pliocene. A Late Pliocene age is assigned as the collection is derived from the very top of the section, i.e. upper Yorktown Fm.

• bed-level stratigraphic resolution

Environment/lithology: coastal; unlithified, shelly/skeletal, silty, calcareous sandstone

• DEPTH: shallow, quiet water environment, possibly back-barrier or bay. SALINITY: no specific data reported, mostly taxa with normal marine preferences, but capable of living in opern bay system. THERMAL TOLERANCES: dinoflagellates suggest temperatures slightly warmer than at present. PALEOBIOGEOGRAPHY: no specific data reported.
• GENERAL LITHOLOGY: Calcareous, muddy sand with abundant macrofossils.

Size class: macrofossils

Reposited in the USNM

Collection methods: core,

• SOURCE: occurrences of large recognizable species and any molluscan remains were noted. Fossiliferous samples were collected at selected intervals for precessing and further examination. Samples were washed, the fraction >850 um was retained, and molluscan fauna specimens recovered were sorted and identified. Generic assignments for extant groups were updated on the basis of Turgeon et al. (1998). COLLECTORS: Collected by NASA-USGS. REPOSITORIES: presumably reposited in USGS and USNM collections.

Primary reference: L. E. Edwards, J. A. Barron, D. Bukry, L.M. Bybell, T.M. Cronin, C.W. Poag, R.E. Weems and G.L. Wingard. 2005. Paleontology of the Upper Eocene to Quaternary Post Impact Section in the USGS-NASA Langley Core, Hampton Virginia. United States Geological Survey Professional Paper 1688:1-71 [A. Miller/A. Hendy/R. McClees-Funinan]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 61295: authorized by Austin Hendy, entered by Austin Hendy on 04.06.2006

Creative Commons license: CC BY (attribution)

Taxonomic list

• COVERAGE: Not exhaustive, but detailed considering limited material available from core. IDENTIFIED: presumably identified by L. Wingard (USGS). NOMENCLATURE: appears to be fairly modern.
Gastropoda
 Sorbeoconcha - Naticidae
Tectonatica pusilla Say 1822 moon snail
 Cerithioidea - Turritellidae
"Turritella alticostata" = Turritella (Turritella) alticostata
"Turritella alticostata" = Turritella (Turritella) alticostata Conrad 1834 turret shell
Bivalvia
 Nuculanida - Nuculanidae
Nuculana acuta Conrad 1832 pointed nut clam
 Nuculanida - Yoldiidae
Yoldia laevis Say 1824 clam
 Nuculida - Nuculidae
"Nucula proxima" = Nucula (Nucula) proxima
"Nucula proxima" = Nucula (Nucula) proxima Say 1820 Atlantic Nut Clam
 Lucinida - Lucinidae
Parvilucina crenulata Conrad 1840 clam
 Cardiida - Tellinidae
Tellina sp. Linnaeus 1758 tellin clam
 Cardiida - Veneridae
"Pitar sayana" = Pitar morrhuanus
"Pitar sayana" = Pitar morrhuanus Dall 1902 venus clam