USGS 14056 - Nuevo Leon, Mexico (Lower Marine Sandstone, Oligocene) (Oligocene of Mexico)

Also known as USGS 14056

Where: Nuevo Leon, Mexico (25.8° N, 99.2° W: paleocoordinates 26.6° N, 93.1° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Lower marine sandstone Member, Early/Lower Oligocene (33.9 - 28.4 Ma)

• Lower Oligocene age faunas in notheastern Mexico are closely allied to the Chickasawhay and Suwanee limestones of the eastern Gulf Coast. They are recognised in a lower marine sandstone, presumably of lower Oligocene age, and in an upper marine sandstone, presumably of middle Oligocene age. The marine beds are separated by non-maine sediments, typically red and green bentonitic clays. The Oligocene series in Mexico is measured in thousands of feet, although the fauna is only known from a few isolated outcrops.

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, medium-grained, concretionary, brown, gray, conglomeratic, calcareous sandstone

• Siliciclastic. No paleoenvironmental data reported.
• Brownish tan or gray, medium-grained, locally conglomeratic, calcareous concretionary sandstone.

Size class: macrofossils

Reposited in the USNM

Collection methods: quarrying,

• Collections reposited in USGS and USNM collections.

Primary reference: J. Gardner. 1945. Mollusca of the Tertiary formations of Northeastern Mexico. Geological Society of American Memoir 11 [M. Kosnik/M. Kosnik/M. Kosnik]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 43077: authorized by Austin Hendy, entered by Austin Hendy on 10.08.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for mollusca.
Gastropoda
 Neogastropoda - Conidae
 Sorbeoconcha - Ficidae
Ficus mississippiensis Conrad 1848 fig shell
 Sorbeoconcha - Naticidae
Sinum mississippiense Conrad 1848 moon snail
Bivalvia
 Ostreida - Pteriidae
Pteria sp. Scopoli 1777 pearl oyster
 Pholadida - Corbulidae
 Cardiida - Cardiidae
"Nemocardium ? diversum" = Nemocardium (Nemocardium) diversum, "Cerastoderma (Dinocardium) bakeri" = Dinocardium
"Nemocardium ? diversum" = Nemocardium (Nemocardium) diversum Conrad 1848 cockle
"Cerastoderma (Dinocardium) bakeri" = Dinocardium cockle
 Carditida - Carditidae
"Venericardia cf. carsonensis" = Venericardia (Rotundicardia) carsonensis
"Venericardia cf. carsonensis" = Venericardia (Rotundicardia) carsonensis Dall 1903 clam