ammonites
USGS Mesozoic loc. 3014, Chisik Island, Cook Inlet (Jurassic of the United States)

Where: Alaska (60.2° N, 152.6° W: paleocoordinates 33.0° N, 87.2° W)

• coordinate estimated from map

• small collection-level geographic resolution

When: Bowser Member (Tuxedni Formation), Callovian (164.7 - 161.2 Ma)

• at top of Bowser member, 820 ft above Cranocephalites beds; stratigraphic position is well established

• bed-level stratigraphic resolution

Environment/lithology: marine; lithified siliciclastic sediments

• probably gray and/or sandy silstone (based on description of Bowser member north from Chinitna Bay)

Size class: macrofossils

Reposited in the USGS

• collection was made by T. W. Stanton in 1904

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 68872: authorized by Martin Aberhan, entered by Sabine Nürnberg on 10.02.2007