Also known as LACM Vertebrate Locality 4510; UGSG M7891; USGS M8995; UWBM B-7450

Where: Pacific County, Washington (46.5° N, 123.8° W: paleocoordinates 46.1° N, 114.8° W)

• coordinate based on nearby landmark

• small collection-level geographic resolution

When: Lincoln Creek Formation, Chattian (28.1 - 23.0 Ma)

• The presence of Liracassis apta and other Juanian Stage mollusks places the Lincoln Creek part of the section in the late Oligocene, and Moore (1984a) indicated that some of the other mollusks suggest affinities with those of the early Miocene Pillarian Stage, so she argued that the Knappton Lincoln Creek molluscan fauna is late Juanian in age. In the Canyon River section of the Lincoln Creek and Astoria formations (Prothero and Armentrout, 1985), the L. apta (Moore, 1984b) Zone (and Juanian Stage) spans magnetic Chrons C10n–C6Cr; this is also true of the type Juanian section in the Pysht Formation (Prothero et al., 2001c). Thus, the best correlation of the long reversed interval followed by the short normal magnetozone of the Knappton Lincoln Creek section is either Chrons C7r–C7n, or C7Ar–C7An. LACM 5842 is stratigraphically above this interval, but below the Astoria Formation, suggesting a latest Chattian age.

• bed-level stratigraphic resolution

Environment/lithology: deep-water; lithified, concretionary shale

Size class: macrofossils

Reposited in the LACM

Primary reference: V. A. Zullo. 1982. Arcoscalpellum Hoek and Solidobalanus Hoek (Cirripedia, Thoracica) from the Paleogene of Pacific County, Washington, with a description of a new species of Arcoscalpellum. Natural History Museum of Los Angeles County Contributions in Science (336)1-9 [A. Hendy/A. Hendy]more details

Purpose of describing collection: general faunal/floral analysis

PaleoDB collection 91623: authorized by Wolfgang Kiessling, entered by Uta Merkel on 07.10.2009, edited by Austin Hendy, Matthew Clapham and Mark Uhen

Creative Commons license: CC BY (attribution)