Where: Montana (47.8° N, 112.7° W: paleocoordinates 40.5° N, 52.1° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Upper Siltstone Member (Sawtooth Formation), Bathonian (168.3 - 166.1 Ma)

• zone 4 from basal 13 ft of upper member of Sawtooth formation, or 107-120 ft above base of Ellis Group; the Upper Siltstone member is probably of Bathonian age

• group of beds-level stratigraphic resolution

Environment/lithology: marine; lithified siltstone

Size class: macrofossils

Reposited in the USGS

• collection was made by C. F. Deiss in 1941

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 68848: authorized by Martin Aberhan, entered by Sabine Nürnberg on 10.02.2007

Creative Commons license: CC BY (attribution)