Where: Montana (47.7° N, 112.7° W: paleocoordinates 40.1° N, 51.8° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Middle Shale Member (Sawtooth Formation), Bajocian to Bajocian (170.3 - 166.1 Ma)

• from middle shale member of Sawtooth formation; the Middle Shale member is probably of Bajocian to Bathonian age

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified shale

Size class: macrofossils

Reposited in the USGS

• collection was made by M. R. Mudge in 1958

Primary reference: R. W. Imlay. 1962. Jurassic (Bathonian or Early Callovian) Ammonites from Alaska and Montana. Geological Survey Professional Paper 374-C:1-32 [M. Aberhan/S. Nurnberg]more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 68837: authorized by Martin Aberhan, entered by Sabine Nürnberg on 10.02.2007

Creative Commons license: CC BY (attribution)