ammonites
Petalocrinus mirabilis-Pentameroides-Coral Assoc., Buck Creek Member, E Iowa (Silurian to of the United States)

Where: Iowa (42.2° N, 91.1° W: paleocoordinates 22.5° S, 53.9° W)

• coordinate based on political unit

• local area-level geographic resolution

When: Buck Creek Quarry Member (Scotch Grove Formation), Telychian to Telychian (436.0 - 426.2 Ma)

• "Late Llandoverian (C6) to Early Wenlockian..."

• member-level stratigraphic resolution

Environment/lithology: deep subtidal ramp; graded, burrowed, cherty/siliceous packstone and graded, burrowed, cherty/siliceous grainstone

• "...crowns very rare..root systems common but generally not concentrated. The environment seems moderately active, basically an echinoderm shoal with other fauna intermixed and preserved only sporadically, probably most often in areas bordering the shoal proper, perhaps in slightly deeper and quieter water. The association with both coral-dominated and pentamerid-dominated communities indicates at least a BA 3-4 boundary position. The coral faunas are more diverse than typical BA2-3...'Costistricklandia', Dicoelosia, and Porpites in small numbers [suggest] outer BA3 to shallow BA4 for some sites...total range BA3 to shallow BA 4."

•

•SEP environmental call based on given description and same vol. page 807.

• "Very fossiliferous. Much of the B.C.Q. Mbr is sparsely fossiliferous skeletal-moldic dolowackestone, but localities with this community are very cherty, nonporous, moderately to well-silicified skeletal-replacement packstones-grainstones...some evidence of graded bedding and occasional crossbeds...much of the section appears to have been reworked by burrowers"

Preservation: replaced with silica

Primary reference: T. J. Frest, C. E. Brett, and B. J. Witzke. 1999. Caradocian-Gedinnian echinoderm associations of Central and Eastern North America. Paleocommunities--a case study from the Silurian and Lower Devonian 638-783 [M. Foote/K. Koverman/P. Wagner] more details

Purpose of describing collection: paleoecologic analysis

PaleoDB collection 26810: authorized by Michael Foote, entered by Michael Foote on 04.11.2002