USGS M4683 (Oligocene of the United States)

Where: Clallam County, Washington (48.2° N, 124.1° W: paleocoordinates 47.9° N, 115.2° 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

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 37590: authorized by Austin Hendy, entered by Austin Hendy on 17.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Only molluscan taxa listed.
Bivalvia
 Pectinida - Pectinoidae
 Cardiida - Mactridae
"Spisula cf. albaria" = Mactromeris albaria
"Spisula cf. albaria" = Mactromeris albaria Conrad 1848 clam
Subspecies: Spisula albaria goodspeedi
 Cardiida - Veneridae
 Cardiida - Tellinidae
Tellina emacerata Conrad 1849 tellin clam
Macoma sp. n. sp. Leach 1819 tellin clam
Macoma albaria Conrad 1849 tellin clam
 Hiatellida - Hiatellidae
Panopea ramonensis Clark 1925 clam
 Nuculida - Nuculidae
"Acila cf. conradi" = Acila (Truncacila) conradi
"Acila cf. conradi" = Acila (Truncacila) conradi Meek 1864 divaricate nutclam
 Protobranchia - Nuculanidae
Nuculana ? calkinsi pointed nut clam
Gastropoda
 Neogastropoda - Turridae
 Naticoidea - Naticidae
Natica vokesi Addicott 1966 moon snail
Polinices ? victorianus Clark and Arnold 1923 moon snail
 Calyptraeoidea - Calyptraeidae
Crepidula sp. Lamarck 1799 slipper shell
Scaphopoda
 Dentaliida - Dentaliidae
Dentalium schencki Moore 1963 tusk shell