Where: Tennessee (35.7° N, 88.1° W: paleocoordinates 32.6° S, 52.4° W)
• coordinate based on political unit
• local area-level geographic resolution
When: Decatur Limestone Formation, Pridoli (423.0 - 419.2 Ma)
• Upper part of Decatur Limestone, crinoidal grainstone intervals about 9 and 1.5 m below top of formation (which is 15 to 20 m thick).
• member-level stratigraphic resolution
Environment/lithology: sand shoal; shelly/skeletal, gray wackestone and shelly/skeletal, gray grainstone
• "...represent winnowed skeletal shoal accumulations produced in relatively high energy shallow water environments approaching normal wave base. It is not clear that all of the echinoderms are in situ, but probably they have been trnasported relatively short distances and concentrated mainly by storm waves. The interbedding of ...grainstone with...wackestone...suggests that the life-style...may have been in lower energy, slightly deeper environments...the evidence from associated brachiopods in general depositional seetings indicates that this is an inner BA 3 shal...interbedded with outer BA 3 lower energy deposits."
• "The Decature Lst consists of about 15 to 20 m of gray to brick-red limestone. The unit is dominated by relatively fine-grained wackestone containing a sparse fauna. The fossiliferous intervals are characterized by crinoid holdfasts, including dendriticc roots...and loboliths...Most of the echinoderm fauna occurs in two intervals, each approx. 2 m thick, of well washed crinoidal grainstone...These beds consist largely of the planar to slightly crossbedded, winnowed accumulations of crinoids..."
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 26772: authorized by Michael Foote, entered by Michael Foote on 31.10.2002
Creative Commons license: CC BY (attribution)
Taxonomic list
• Brachiopods mentioned but not listed. 28 crinoid species in 17 genera are said to be present in decatur Limestone, but only dominant genera are listed.
Show authors, comments, and common names
| Blastoidea |
| Fissiculata - Phaenoschismatidae |
|
| Crinoidea |
| Diplobathrida - Lampterocrinidae |
|
| Monobathrida - Marsupiocrinidae |
|
| Monobathrida - Eucalyptocrinitidae |
|
| Monobathrida - Periechocrinidae |
|
| Monobathrida - Hexacrinitidae |
|
| Monobathrida - Scyphocrinitidae |
|
| Sagenocrinida - Lecanocrinidae |
|
| Pisocrinida - Pisocrinidae |
|
| Bryozoa |
| - |
|
| Brachiopoda |
| - |
|
| Rhynchonellata |
| Pentamerida - Gypidulidae |
|