M1185 - West Cove Section (Oligocene of the United States)

Also known as M1185

Where: Aleutians East County, Alaska (55.6° N, 160.3° W)

• Paleocoordinates: 63.1° N, 155.9° W (Wright 2013)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

When: Stepovak Formation, Oligocene (33.9 - 23.0 Ma)

• This is the type area of the Stepovak Formation ("series"). The exposures are reasonably good. The Stepovak Formation is greater than 2500 ft thick, Oligocene in age, and overlies the Eocene Tolstoi Formation, and is in turn overlain by the Miocene Bear Lake Formation. The formation comprises sandstones with thin conglomerates and siltstone and shale. Collection probably middle Oligocene

• bed-level stratigraphic resolution

Environment/lithology: marine; poorly lithified, concretionary, black, calcareous siltstone and concretionary, black, calcareous shale

• No paleoenvironmental reported.
• Black siltstone and dark shale with calcareous concretions and isolated volcanic fragments.

Size class: macrofossils

Collection methods: quarrying,

• Collections examined by F.S. MacNeil and D. Taylor (USGS), 1962. Collections are reposited at USGS Menlo Park, or presumably USNM (not reported)

Primary reference: C.A. Burk. 1965. Geology of the Alaska Peninsula-island arc and continental margin (Part 1). Geological Society of America Memoir 99(1) [A. Miller/A. Hendy/A. Hendy]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 44116: authorized by Austin Hendy, entered by Austin Hendy on 01.09.2004

Creative Commons license: CC0 (CC0)

Taxonomic list

• No other fossils mentioned.
Gastropoda
 Trochoidea - Turbinidae
 Epitonioidea - Epitoniidae
"Epitonium atwoodi" = Acrilla (Ferminoscala) atwoodi
"Epitonium atwoodi" = Acrilla (Ferminoscala) atwoodi Dall 1908 wentletrap
Bivalvia
 Cardiida - Mactridae
? Spisula sp. Gray 1837 clam
= ?Mesodesma alaskensis
 Cardiida - Corbiculidae
 Cardiida - Tellinidae
Macoma sp. Leach 1819 tellin clam
 Ostreida - Ostreidae
Ostreidae indet. Rafinesque 1815 oyster