USGS M4414 (Oligocene of the United States)

Also known as Slip Point

Where: Clallam County, Washington (48.3° N, 122.3° W: paleocoordinates 48.0° N, 113.3° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Clallam Formation, Chattian (28.1 - 23.0 Ma)

• GENERAL STRATIGRAPHY: The Clallam Formation is a predominantly marine sandstone with minor conglomerate and siltstone exposed along the Strait of Juan de Fuca in northwestern Washington. Marine molluscs occur throughout the 600 to 800 m thick formation but are especially abundant in the lowermost 240 m. Pillarian Stage age, a provincial time stratigraphic unit of late early Miocene age. Revised to Chattian following more recent work [Hendy, 7/2016].

• bed-level stratigraphic resolution

Environment/lithology: offshore; lithified sandstone

• All Clallam Formation assemblages represent inner sublittoral depths (less than about 100 m). Qualitative analysis of these assemblages indicates a gradual shallowing during deposition of the formation. The highest strata in the formation contain coal and are presumably non-marine.
• Sandstone with minor conglomerate and siltstone.

Size class: macrofossils

Preservation: mold/impression

Collected by Addicott in 1970; reposited in the USGS

Collection methods: surface (float), surface (in situ),

• REPOSITORY: USGS (Menlo Park).

Primary reference: W.O. Addicott. 1976. Molluscan paleontology of the lower Miocene Clallam Formation, northwestern Washington. United States Geological Survey Professional Paper 976:1-44 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 37580: authorized by Austin Hendy, entered by Austin Hendy on 17.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Only molluscan taxa listed.
Gastropoda
 Sorbeoconcha - Naticidae
Polinices victorianus Clark and Arnold 1923 moon snail
Natica cf. clarki Etherington 1931 moon snail
 Sorbeoconcha - Cassidae
Semicassis pyshtensis Addicott 1976 snail
 Neogastropoda - Turridae
Ophiodermella olympicensis Addicott 1976 turrid
 Neogastropoda - Siphonaliidae
Bruclarkia yaquinana Anderson and Martin 1914 snail
 Neotaenioglossa - Calyptraeidae
Crepidula rostralis Conrad 1865 slipper shell
Crepidula ? princeps Conrad 1855 slipper shell
Trochita sp. n. sp. Schumacher 1817 slipper shell
Bivalvia
 Nuculanida - Nuculanidae
Nuculana cf. calkinsi pointed nut clam
 Nuculida - Nuculidae
"Acila conradi" = Acila (Truncacila) conradi
"Acila conradi" = Acila (Truncacila) conradi Meek 1864 divaricate nutclam
 Carditida - Carditidae
Cyclocardia subtenta Conrad 1849 clam
 Cardiida - Mactridae
"Spisula albaria" = Mactromeris albaria Conrad 1848 clam
Spisula sookensis Clark and Arnold 1923 clam
 Cardiida - Veneridae
Katherinella angustifrons Conrad 1849 venus clam
"Dosinia whitneyi" = Dosinia (Dosinia) whitneyi Gabb 1866 venus clam
"Securella ensifera" = Chione (Securella) ensifera Dall 1909 venus clam
 Cardiida - Tellinidae
Macoma sookensis Clark and Arnold 1923 tellin clam
"Tellina emacerata" = Tellina (Oudardia) emacerata Conrad 1849 tellin clam
 Cardiida - Cardiidae
"Clinocardium aff. nuttallii" = Clinocardium (Clinocardium) nuttallii
"Clinocardium aff. nuttallii" = Clinocardium (Clinocardium) nuttallii Conrad 1837 cockle
[entered as Clinocardium nuttalli]
 Hiatellida - Hiatellidae
Panopea ramonensis Clark 1925 clam
Panopea abrupta Conrad 1849 clam
 Solenida - Solenidae
"Solen conradi" = Solena (Plectosolen) conradi
"Solen conradi" = Solena (Plectosolen) conradi Dall 1900 clam
 Lucinida - Lucinidae
Lucinoma acutilineata Conrad 1849 clam
 Mytilida - Mytilidae
"Mytilus aff. tichanovitchi" = Mytilus (Tumidimytilus) tichanovitchi
"Mytilus aff. tichanovitchi" = Mytilus (Tumidimytilus) tichanovitchi Makiyama 1934 mussel
 Pectinida - Pectinoidae
Vertipecten fucanus Dall 1898 scallop
 Arcida - Glycymerididae
Glycymeris sp. Da Costa 1778 clam
Scaphopoda
 Dentaliida - Dentaliidae
Dentalium cf. schencki Moore 1963 tusk shell