USGS M4050 (Oligocene of the United States)

Also known as Pysht area

Where: Clallam County, Washington (48.2° N, 122.1° W: paleocoordinates 47.9° N, 113.2° W)

• coordinate based on political unit

• outcrop-level geographic resolution

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

• SPECIFIC STRATIGRAPHY: From three 1-m thick beds in an interval between 191 and 207 m above the base of the formation. 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 37577: authorized by Austin Hendy, entered by Austin Hendy on 17.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Only molluscan taxa listed.
 Arcida - Arcidae
 Pectinida - Pectinoidae
 Mytilida - Mytilidae
Modiolus aff. restorationensis Van Winkle 1918 mussel
 Carditida - Carditidae
Cyclocardia subtenta Conrad 1849 clam
 Cardiida - Mactridae
"Spisula albaria" = Mactromeris albaria
"Spisula albaria" = Mactromeris albaria Conrad 1848 clam
 Cardiida - Veneridae
 Cardiida - Tellinidae
Macoma albaria Conrad 1849 tellin clam
Macoma astori Dall 1909 tellin clam
 Hiatellida - Hiatellidae
Panopea abrupta Conrad 1849 clam
Panopea ramonensis Clark 1925 clam
 Solenida - Solenidae
"Solen conradi" = Solena (Plectosolen) conradi
"Solen conradi" = Solena (Plectosolen) conradi Dall 1900 clam
 Thraciida - Thraciidae
"Thracia trapezoides" = Thracia (Homoeodesma) trapezoides
"Thracia trapezoides" = Thracia (Homoeodesma) trapezoides Conrad 1849 clam
 Lucinida - Thyasiridae
"Conchocele disjuncta" = Conchocele conradii
"Conchocele disjuncta" = Conchocele conradii Rosenkrantz 1942 clam
 Lucinida - Lucinidae
Lucinoma acutilineata Conrad 1849 clam
 Neogastropoda - Buccinidae
 Neogastropoda - Fasciolariidae
Priscofusus goweri Addicott 1976 snail
 Neogastropoda - Cancellariidae
Cancellaria birchi Addicott 1970 snail
 Neogastropoda - Volutidae
"Musashia indurata" = Fulgoraria (Musashia)
"Musashia indurata" = Fulgoraria (Musashia) volute
 Neogastropoda - Turridae
Ophiodermella olympicensis Addicott 1976 turrid
 Naticoidea - Naticidae
Sinum ? scopulosum Conrad 1849 moon snail
 Calyptraeoidea - Calyptraeidae
Crepidula praerupta Conrad 1849 slipper shell
Trochita sp. n. sp. Schumacher 1817 slipper shell
  - Neptuneidae