Also known as M331; 77AM22
Where: Alaska (55.2° N, 161.6° W: paleocoordinates 56.7° N, 159.0° W)
• coordinate stated in text
• outcrop-level geographic resolution
When: Bear Lake Formation, Middle Miocene (16.0 - 11.6 Ma)
• STRATIGRAPHIC RELATIONS: From Bear Lake Fm, which is presumed to overlie the Stepovak Fm (Paleogene), though the contact is not exposed. AGE: Middle Miocene. 15-16 Mas, or earliest Middle Miocene based on the presence of Turritella (Hataiella) sagai. This is the greatest known age for any Bear Lake outcrop. An overlying andesitic flow has been radiometrically dated at 10.4 Ma. STRATIGRAPHIC POSITION: Unknown position within formation.
• bed-level stratigraphic resolution
Environment/lithology: transition zone or lower shoreface; lithified, coarse-grained sandstone
Size class: macrofossils
Reposited in the LACM, USNM
Collection methods: quarrying,
• COLLECTOR: L. Marincovich, Jr (1977). REPOSITORY: USGS (Menlo Park), LACM, USNM
Primary reference: L. Marincovich. 1988. Recognition of an earliest Middle Miocene warm-water event in a southestern Alaskan molluscan fauna. Saito-Ho-on Kai Special Publication 1:1-24 [A. Hendy/A. Hendy/P. Wagner]more details
Purpose of describing collection: paleoecologic analysis
PaleoDB collection 67915: authorized by Austin Hendy, entered by Austin Hendy on 16.12.2006
Creative Commons license: CC BY (attribution)
Taxonomic list
Bivalvia | |
Yoldia sp. Möller 1842 clam | |
Acila sp. Adams and Adams 1858 divaricate nutclam | |
Mya sp. Linnaeus 1758 softshell clam
Mya (Mya) truncata Linnaeus 1758 softshell clam | |
? Pitar sp. Römer 1857 venus clam | |
Macoma sp. Leach 1819 tellin clam | |
Clinocardium sp. Keen 1936 cockle | |
Lucinoma acutilineata Conrad 1849 clam | |
Scaphopoda | |
Dentalium (Rhabdus) cf. schencki Moore 1963 tusk shell | |
Gastropoda | |
Turritella (Hataiella) sagai Kotaka 1951 turret shell | |
Beringius crebricostatus Dall 1877 true whelk
? Colus sp. Röding 1798 true whelk |