Columbia (USGS 25033) - Hickman (1980) (Eocene of the United States)

Also known as USGS 25033

Where: Columbia County, Oregon (45.8° N, 123.3° W: paleocoordinates 46.1° N, 111.0° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Middle Member (Keasey Formation), Priabonian (38.0 - 33.9 Ma)

• Middle member includes 500 m of predominantly light gray highly tuffaceous siltstone and mudstone beds with occasional ash layers and calcaerous concretionary beds. The Keasey Formation consists of a maximum of 700 m of gray tuffaceous marine siltstone and massive mudstone discontinuously exposed in quaries, road and railway cuts, and along major drainages. The Keasey Fm overlies the late Eocene Cowlitz Fm, and underlies the Pittsburg Bluff Fm. Fm is subdivided into three informal members.

• bed-level stratigraphic resolution

Environment/lithology: deep-water; poorly lithified, concretionary, tuffaceous, gray, calcareous siltstone and concretionary, tuffaceous, gray, calcareous mudstone

• No general geologic data provided
• Predominantly light gray highly tuffaceous siltstone and mudstone beds with occasional ash layers and calcaerous concretionary beds

Size class: macrofossils

Reposited in the USNM

Collection methods: quarrying,

• USGS collections are reposited in USNM. Other collections are reposited at Stanford University (SU), UC Berkeley Museum of Paleontology (UCMP), Cal. Acad. Sci. (CAS), Oregon State Dept. of Geology and Mineral Industries (DOGAMI)

Primary reference: C. S. Hickman. 1980. Paleogene Marine Gastropods of the Keasey Formation in Oregon. Bulletins of American Paleontology 78(310):1-112 [L. Ivany/E. Kowalski/M. Uhen]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 40193: authorized by Austin Hendy, entered by Austin Hendy on 19.06.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for gastropoda
Gastropoda
 Epitonioidea - Epitoniidae
 Sorbeoconcha - Naticidae
 Neogastropoda - Buccinidae
Trophonopsis platacantha Hickman 1980 true whelk
 Neogastropoda - Cancellariidae
Sveltella sp. Cossmann 1889 snail
 Neogastropoda - Turridae
Ptychosyrinx facula Hickman 1976 turrid
Procerapex bentsonae Durham 1944 turrid
 Sorbeoconcha - Bursidae
Olequahia schencki Durham 1944 frog shell
 Sorbeoconcha - Cassidae
Echinophoria dalli Dickerson 1917 snail