Threeforks Shale, Jefferson Island Co., Montana (measured section 2 of author): Middle Famennian, Montana

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
unclassified
Hunanospirifer monticola
Hunanospirifer ? gallatinensis
Strophomenata - Productida - Sentosiidae
Echinoconchus ? laminatus (Kindle 1909)
recombined as Laminatia laminata
Rhynchonellata - Spiriferida - Mucrospiriferidae
Eleutherokomma raymondi
Rhynchonellata - Rhynchonellida - Trigonirhynchiidae
Camarotoechia sobrina Stainbrook 1947
recombined as Ptychomalotoechia sobrina
Rhynchonellata - Rhynchonellida - Rhynchotetradidae
Paraphorhynchus jeffersonense
Rhynchonellata - Orthida - Schizophoriidae
Schizophoria australis (Kindle 1909)
recombined as Schizophoria (Schizophoria) australis
see common names

Geography
Country:United States State/province:Montana County:Jefferson Island
Coordinates: 45.9° North, 112.0° West (view map)
Paleocoordinates:14.8° South, 46.6° West
Basis of coordinate:based on nearby landmark
Geographic resolution:outcrop
Time
Period:Devonian Epoch:Late/Upper Devonian
Stage:Famennian 10 m.y. bin:Devonian 5
*Period:Late/Upper Devonian
Key time interval:Middle Famennian Zone: Platyclymenia
Age range of interval:368.50000 - 365.30000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Three Forks Shale
Stratigraphic resolution:formation
Stratigraphy comments: species of ammonoid found by the author correspond to the Oberdevon III, the lower Platyclymenia horizon in the European stratigraphic column [JA: originally entered as late Devonian, but the lower Platyclymenia horizon corresponds to the Pa. trachytera conodont zone and is middle Famennian]
Lithology and environment
Primary lithology:planar lamination,red or brown,yellow "shale"
Lithology description: author gives no detailed description of lithology where she collected; however, through historic descriptions included in the text, the formation is divided into two shale units divided by limestone. this collection came from the lower shale, which is described as variegated in color (reds, yellow, brown) and finely laminated.
Environment:marine indet.
Taphonomy
Modes of preservation:body
Collection methods and comments
Collection methods:surface (in situ),field collection
Reason for describing collection:biostratigraphic analysis
Metadata
Database number:6982
Authorizer:A. Miller Enterer:K. Layou
Modifier:J. Alroy Research group:marine invertebrate
Created:2000-04-18 13:34:51 Last modified:2010-07-15 08:19:54
Access level:the public Released:2000-11-20 13:53:33
Creative Commons license:CC BY
Reference information

Primary reference:

438. P. J. Renzetti. 1961. Fauna of the Threeforks Shale (Devonian) of Southwestern Montana. 1-342 [A. Miller/K. Layou/M. Uhen]