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Muirkirk, Arundel (Cretaceous of the United States)

Where: Prince George's County, Maryland (39.1° N, 76.9° W: paleocoordinates 33.0° N, 29.5° W)

• coordinate stated in text

• local area-level geographic resolution

When: Arundel Clay Formation (Potomac Group), Early/Lower Aptian (125.5 - 122.5 Ma)

• Originall described as "Potomac Formation" and "Upper Jurassic"; now considered early-mid Aptian

• member-level stratigraphic resolution

Environment/lithology: lacustrine; gray, red claystone

• "variegated red and gray clays"

Size class: macrofossils

Collected by J. B. Hatcher, A. Bibbins in 1887-1894; reposited in the USNM

Collection methods: quarrying, mechanical,

Primary reference: O. C. Marsh. 1888. Notice of a new genus of Sauropoda and other new dinosaurs from the Potomac Formation. American Journal of Science 35:89-94 [M. Carrano/M. Carrano/M. Carrano] more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 28432: authorized by Matthew Carrano, entered by Matthew Carrano on 13.02.2003, edited by Roger Benson

Creative Commons license: CC BY (attribution)