Also known as Antelope Valley

Where: Madison County, Montana (45.8° N, 111.8° W: paleocoordinates 9.8° S, 45.7° W)

• coordinate stated in text

• small collection-level geographic resolution

When: Sappington Formation, Kinderhookian (360.7 - 353.8 Ma)

• bed-level stratigraphic resolution

Environment/lithology: marginal marine; lithified, argillaceous, silty shale and silty, sandy sandstone

Size class: mesofossils

• Blastoids some with attached stems and brachioles.

Preservation: original calcite

Collection methods: quarrying, surface (float), mechanical,

Primary reference: J. Sprinkle and R. C. Gutschick. 1967. Costatoblastus, a channel fill blastoid from the Sappington Formation of Montana. Journal of Paleontology 41(2):385-401 [J. Alroy/M. Sommers/J. Alroy] more details

Purpose of describing collection: biostratigraphic analysis

PaleoDB collection 123117: authorized by John Alroy, entered by David Mathieson on 11.01.2012

Creative Commons license: CC BY-NC-ND (attribution-noncommercial-no derivatives)