M1163 - McGinty Point section (Oligocene of the United States)

Also known as M1163

Where: Aleutians East County, Alaska (55.5° N, 161.0° W: paleocoordinates 58.7° N, 154.9° W)

• coordinate based on nearby landmark

• outcrop-level geographic resolution

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

• These exposures were examined along the west shore of Beaver Bay from near the mouth of the Beaver River to McGinty Point. Except for the upper few hundred feet the rocks are all part of the Oligocene Stepovak Formation. The formation is at least 15,00 ft thick in this area and is underlain by up to 5000 ft of the Eocene of Tolstoi Formation. From lower in section than collections M1172, M1173 and M1188.

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified, concretionary, black shale

• No paleoenvironmental data reported.
• Black shale and siltstone with many calcareous concretions. Interbedded with sandstones and few conglomerates.

Size class: macrofossils

Preservation: concretion

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 44081: authorized by Austin Hendy, entered by Austin Hendy on 31.08.2004

Creative Commons license: CC BY (attribution)

Taxonomic list

• No other fossils mentioned.
Bivalvia
 Nuculanida - Yoldiidae
Yoldia sp. Möller 1842 clam
 Ostreida - Ostreidae
Ostreidae indet. Rafinesque 1815 oyster
 Cardiida - Cardiidae
Nemocardium sp. Meek 1876 cockle
 Cardiida - Tellinidae
Macoma sp. Leach 1819 tellin clam
 Thraciida - Periplomatidae
Periploma sp. Schumacher 1816 clam
Gastropoda
 Sorbeoconcha - Naticidae
Natica sp. Scopoli 1777 moon snail
 Neogastropoda - Buccinidae
Siphonalia aff. sakakurai Mizuno 1954 true whelk
 Neogastropoda - Ptychatractidae
? Exilia sp. Conrad 1860 snail