Thaerodonta-Cupulocrinus angustus-Cornulites Community of the Brainard: Richmondian, Iowa
Where & when
Geology
Taphonomy & methods
Metadata & references
Geography
| Country: | United States | State/province: | Iowa | County: | Dubuque County |
| Coordinates: | 42.9° North, 91.7° West (view map) | ||||
| Paleocoordinates: | 19.4° South, 60.0° West | ||||
| Basis of coordinate: | based on political unit | ||||
| Geographic resolution: | outcrop |
Time
| Period: | Ordovician | Epoch: | Late/Upper Ordovician |
| Stage: | Katian | 10 m.y. bin: | Ordovician 5 |
| *Period: | Late/Upper Ordovician | *Epoch: | Ashgill | *Local age/stage: | Richmondian |
| Key time interval: | Richmondian | ||
| Age range of interval: | 449.80000 - 446.00000 m.y. ago | ||
| * legacy (obsolete) database fields | |||
Stratigraphy
Lithology and environment
| Primary lithology: | bioturbation,dolomitic lithified silty,calcareous "shale" |
| Secondary lithology: | dolomitic,ferruginous lithified wackestone |
| Includes fossils? | Y |
| Lithology description: The upper Brainard sections most likely to have this community consist of silty calcareous or dolomitic biotutbated shales with interbedded brachiopod-bryozoan-echinoderm ferruginous dolowackestones and some packstones... Occasional phosphatic or highly pyritic intervals with either phosphatized diminutive or normal-sized mollusc faunas occur sporadically throughout the outcrop area. | |
| Environment: | offshore indet. |
| Geology comments: The variable lithology but generally intact fossil preservation in the carbonate intervals suggests a moderately offshore environment still subject, however, to at least occasional storm disturbances. A BA 3-4 position seems likely. | |
Taphonomy
| Modes of preservation: | body |
| Size of fossils: | macrofossils |
Collection methods and comments
| Reason for describing collection: | paleoecologic analysis |
Metadata
| Database number: | 13259 | ||
| Authorizer: | M. Foote | Enterer: | K. Koverman |
| Modifier: | P. Wagner | Research group: | marine invertebrate |
| Created: | 2002-02-04 08:53:00 | Last modified: | 2018-06-19 19:01:52 |
| Access level: | the public | Released: | 2002-02-04 08:53:00 |
| Creative Commons license: | CC BY |
Reference information
Primary reference:
| 4379. | 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] |