ammonites
Maquoketa Formation Cephalopods, Iowa (Ordovician of the United States)

Where: Iowa (43.0° N, 92.0° W: paleocoordinates 19.8° S, 63.7° W)

• coordinate estimated from map

• local area-level geographic resolution

When: Maquoketa Formation, Edenian (460.9 - 449.5 Ma)

• formation-level stratigraphic resolution

Environment/lithology: limestone and shale

• Environmental call by T. Hanson.
• Shale interbedded with limestone; sometimes dolomitic. Lithology from F. M. Swain. 1987. Middle and Upper Ordovician Ostracoda of Minnesota and Iowa. Middle and Late Ordovician lithostratigraphy and biostratigraphy of the Upper Mississippi Valley: Minnesota Geological Survey Report of Investigations 35 :99-101. Edited by R. E. Sloan.

Size class: macrofossils

Primary reference: A. K. Miller, W. Youngquist, and C. Collinson. 1954. Ordovician cephalopod fauna of Baffin Island. Geological Society of America Memoir 62:1-234 [S. Holland/T. Hanson/T. Hanson] more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 24170: authorized by Steven Holland, entered by Tori Hanson on 01.08.2002