Eugene East (UO 2550) - #23 (Hickman) (Eocene of the United States)

Also known as UO 2550

Where: Lane County, Oregon (44.1° N, 123.1° W: paleocoordinates 44.4° N, 110.8° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Eugene Formation, Priabonian (38.0 - 33.9 Ma)

• Eugene Formation can be subdivided faunally: a lower unit correlating to the Keasey Fm, a middle unit correlating to the Gries Ranch Beds of WA, and a upper unit correlated with the Pittsburg Bluff Fm. Thickness of formation may be up to 15,000 feet, but probably around 5,000 feet. Most of the outcrops are scattered so it is difficult to estimate their relative stratigraphic placement

• bed-level stratigraphic resolution

Environment/lithology: coastal; lithified, tuffaceous, brown, gray, blue sandstone and tuffaceous, brown, gray, blue siltstone

• Tuffaceous and highly feldspathic sandstone or siltstone which is bluish-gray to olive when fresh and weathers to a buff or orange-brown color. Gray sandstone and siltstone beds may range from several to 50 feet in thickness and are interbedded with minor amounts of sandy sahel and clay shale, occasional beds of conglomerate, and thin lenses of gray or buff-colored volcanic ash

Size class: macrofossils

Preservation: mold/impression, trace

Reposited in the CAS

Collection methods: quarrying,

• Collections held at University of Oregon, University of California, Californian Academy of Sciences (CAS), United States Geological Survey (USGS), and Stanford University (NP).

Primary reference: C. J. S. Hickman. 1969. The Oligocene marine molluscan fauna of the Eugene Formation in Oregon. University of Oregon Museum of Natural History Bulletin 16:1-112 [A. Miller/A. Hendy/P. Wagner]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 38997: authorized by Austin Hendy, entered by Austin Hendy on 18.05.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Exhaustive for mollusca
Gastropoda
 Neotaenioglossa - Calyptraeidae
Crepidula ungana Dall 1908 slipper shell
 Sorbeoconcha - Naticidae
Polinices washingtonensis Weaver 1916 moon snail
"Neverita thomsonae" = Glossaulax reclusiana Deshayes 1839 moon snail
 Neogastropoda - Olividae
"Molopophorus fishii" = Ancilla fishii
"Molopophorus fishii" = Ancilla fishii Gabb 1866 olive snail
 Neogastropoda - Siphonaliidae
 Heterostropha - Acteonidae
Acteon parvum Dickerson 1917 snail
Bivalvia
 Nuculanida - Yoldiidae
Yoldia (Kalayoldia) oregona Shumard 1858 clam
 Thraciida - Thraciidae
"Thracia condoni" = Thracia (Cetothrax) condoni
"Thracia condoni" = Thracia (Cetothrax) condoni Dall 1909 clam
 Cardiida - Ungulinidae
Diplodonta parilis Conrad 1848 clam
 Cardiida - Veneridae
Pitar (Pitar) dalli Weaver 1916 venus clam
 Cardiida - Mactridae
"Spisula eugenensis" = Mactromeris eugenensis
"Spisula eugenensis" = Mactromeris eugenensis Clark 1925 clam
 Cardiida - Tellinidae
Tellina eugenia Dall 1909 tellin clam
 Mytilida - Mytilidae
Modiolus eugenensis Clark 1925 mussel