USGS #15530 - Pittsburg Bluff Formation (Oligocene of the United States)

Also known as USGS 15530

Where: Columbia County, Oregon (45.9° N, 123.1° W: paleocoordinates 45.5° N, 114.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Pittsburg Bluff Formation, Chattian (28.1 - 23.0 Ma)

• Upper part of Pittsburg Fm. The Pittsburg Bluff Formation conformably overlies the Keasey Formation (late Eocene and early Oligocene) and is conformably overlain by the Scappose Formation (late Oligocene and early Miocene). Parts of the formation are lithologically similar and therefore the stratigraphic position of exposures are sometimes uncertain. The estimated thickness for the entire formation is 200 ml the thickest continuous section of the formation is 100 m thick.

• bed-level stratigraphic resolution

Environment/lithology: offshore; poorly lithified, fine-grained, concretionary, gray sandstone

• Massive olive-gray fine-grained sandstone, with concretions, trough shaped prisms, silstone rip-up clasts.

Size class: macrofossils

Reposited in the USGS

Collection methods: quarrying,

• Material housed in the USGS, Menlo Park. Also collections from UCMP, CAS, Stanford University (SU), University of Washington (UW), University of Oregon (UO), and the Academy of Natural Sciences of Philadelphia (ANSP)

Primary reference: E. J. Moore. 1976. Oligocene marine mollusks from the Pittsburg Bluff Formation in Oregon. United States Geological Survey Professional Paper 922:1-66 [A. Miller/A. Hendy/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 37681: authorized by Austin Hendy, entered by Austin Hendy on 20.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Very complete for mollusca.
Bivalvia
 Cardiida - Veneridae
"Callista (Macrocallista) pittsburgensis" = Macrocallista pittsburgensis
"Callista (Macrocallista) pittsburgensis" = Macrocallista pittsburgensis Dall 1900 venus clam
 Cardiida - Tellinidae
 Cardiida - Cardiidae
"Nemocardium (Keenae) lorenzanum" = Anechinocardium lorenzanum
"Nemocardium (Keenae) lorenzanum" = Anechinocardium lorenzanum Arnold 1908 cockle
 Nuculida - Nuculidae
Acila (Truncacila) shumardi Dall 1909 divaricate nutclam
 Protobranchia - Nuculanidae
Litorhadia washingtoni pointed nut clam
Gastropoda
 Neogastropoda - Drilliidae
Suavodrillia winlockensis Effinger 1938 snail
 Sorbeoconcha - Turritellidae
Turritella pittsburgensis Moore 1976 turret shell
Scaphopoda
 Dentaliida - Dentaliidae