Lituya (M6528) (Miocene to of the United States)

Also known as USGS M6528; 75AM65 (Marincovich field #)

Where: Lituya County, Alaska (58.6° N, 137.6° W: paleocoordinates 58.4° N, 133.2° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Topsy Formation, Burdigalian to Burdigalian (20.4 - 11.6 Ma)

• Topsy Formation consists of about 365 metres of hard calcareous siltstone and sandstone that intertongue with and in part, conformably overlie the Cenotaph Volcanics. Topsy Formation underlies Yakataga Formation (early Miocene-Holocene). Age originally assigned to post-early Oligocene to pre-middle Miocene based on volcanics (Plafker, 1967). Biostratigraphy in this reference constrains age to early or middle Miocene

• bed-level stratigraphic resolution

Environment/lithology: coastal; lithified, calcareous siltstone and lithified, calcareous sandstone

• Because discontinuous outcrops and structurally complex geology in this area preclude reliable lithiologic correlations with other formations in this region and because no well-preserved, age-diagnostic fossils have been reported before from these strata, the age and depositional environment of the Topsy Formation have been the subjects for speculation.
• Topsy Formation "consists of marine siltstone and sandstone"; "hard calcareous siltstone and sandstone"

Size class: macrofossils

Reposited in the USNM

Collection methods: quarrying,

• Fossil collections are housed in the USGS, Menlo Park, and type specimens in the NMNH, Washington

Primary reference: L. Marincovich. 1979. Miocene molluscks of the Topsy Formation, Lituya district, Gulf of Alaska Tertiary Province, Alaska. United States Geological Survey Professional Paper 1125(C):C1-C14 [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 37383: authorized by Austin Hendy, entered by Austin Hendy on 14.03.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• Representative of molluscan elements; no mention of other invertebrate groups
 Pectinida - Pectinoidae
? Chlamys sp. Röding 1798 scallop
 Cardiida - Mactridae
? Spisula sp. Gray 1837 clam
 Cardiida - Tellinidae
"Macoma aff. twinensis" = Macoma (Macoma) twinensis Clark 1925 tellin clam
Macoma (Macoma) golikovi Scarlato and Kafanov 1988 tellin clam
Macoma aff. albaria Conrad 1849 tellin clam
 Thraciida - Periplomatidae
 Lucinida - Lucinidae
Lucinoma acutilineata Conrad 1849 clam
 Nuculida - Nuculidae
 Protobranchia - Nuculanidae
Nuculana (? Sacella) sp. Link 1807 pointed nut clam
 Neogastropoda - Buccinidae
? Colus sp. Röding 1798 true whelk
 Naticoidea - Naticidae
"Natica (Cryptonatica) clausa" = Cryptonatica affinis
"Natica (Cryptonatica) clausa" = Cryptonatica affinis Gmelin 1791 moon snail
 Tonnoidea - Ranellidae
Fusitriton oregonensis Redfield 1846 triton shell
 Turbinoidea - Turbinidae
Turbinidae indet. Rafinesque 1815 snail
 Trochoidea - Trochidae
Calliostoma sp. Swainson 1840 top snail
"Pisces indet." = Osteichthyes
"Pisces indet." = Osteichthyes Huxley 1880 bony fish
 Clypeasteroida -
Clypeasterina indet. Agassiz 1872 sand dollar