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John Day Unit A (Oligocene of the United States)

Also known as Lower Blue Basin Section

Where: Grant County, Oregon (44.6° N, 119.6° W: paleocoordinates 44.4° N, 108.5° W)

• coordinate estimated from map

• outcrop-level geographic resolution

When: John Day Formation, Whitneyan (33.3 - 30.8 Ma)

• member-level stratigraphic resolution

Environment/lithology: terrestrial; lithology not reported

Size class: macrofossils

Primary reference: L. B. Albright, M. O. Woodburne, T. J. Fremd, C. C. Swisher, B. J. MacFadden and G. R. Scott. 2008. Revised chronostratigraphy and biostratigraphy of the John Day Formation (Turtle Cove and Kimberly Members), Oregon, with implications for updated calibration of the Arikareean North American land mammal age. 116(3):211-237 [J. Alroy/J. Alroy] more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 17349: authorized by John Alroy, entered by John Alroy on 26.03.1995

Creative Commons license: CC BY (attribution)