Twilight Section, Bathurst Island, Unit 4, Blue Fiord Formation: Emsian, Canada

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Inarticulata - Inarticulata
informal Inarticulata indet. Huxley 1869
Strophomenata - Productida - Productellidae
Productella sp.
Strophomenata - Strophomenida - Douvillinidae
? Douvillina sp.
Trilobita - Proetida - Proetidae
Dechenella paragranulata Ormiston 1967
? Deltadechenella sp. Ormiston 1967
see common names

Geography
Country:Canada State/province:Nunavut
Coordinates: 76.3° North, 99.3° West (view map)
Paleocoordinates:8.4° South, 19.6° West
Basis of coordinate:estimated from map
Geographic resolution:outcrop
Time
Period: Devonian Epoch: Early Devonian
Stage: Emsian 10 m.y. bin: Devonian 2
*International age/stage:Eifelian
Key time interval: Emsian
Age range of interval: 407.6 - 393.3 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Blue Fiord
Local section:Twilight Local bed:4
Local order:bottom to top
Stratigraphic resolution:group of beds
Stratigraphy comments: "Unit n" [from bottom] is my terminology, not Ormiston's. Unit is 35 feet thick.
Lithology and environment
Primary lithology:red or brown argillaceous "limestone"
Secondary lithology:red or brown "limestone"
Lithology description: Section: "On northern Bathurst Island, the B.F. Fm. consists of light to dark brown, finely crystalline, medium-bedded, fossiliferous limestone interbedded with brown, medium to coarsly crystalline, bioclastic limestone and grey calcareous shale." This unit: "brown, finely crystallin, thin-bedded, argillaceous [limestone]...with a minor amount of pale brown limestone"
Environment:shallow subtidal indet. Tectonic setting:passive margin
Geology comments: Some bioherms observed in section.
SEP: From Rose (1999) Sedimentology and diagenesis of the lower Blue Fiord Formation carbonates in a prospective mississippi valley-type (Pb-Zn) setting, Bathurst Island, N.W.T. Univ. of Calgary MS thesis: "The Devonian Blue Fiord Formation (Emsian-Eifelian) consists of subtidal to supratidal carbonates deposited on a wide platform shelf. It is divided into three informal members based on facies associations; BF (sub 1) (Subtidal Restricted), BF (sub 2) (Lagoonal-Tidal Flat), and BF (sub 3) (Subtidal Open/Restricted). "
Taphonomy
Modes of preservation:body
Size of fossils:macrofossils
Collection methods and comments
Reason for describing collection:biostratigraphic analysis
Metadata
Database number:26585
Authorizer:M. Foote Enterer:M. Foote
Modifier:P. Wagner Research group:marine invertebrate
Created:2002-10-18 08:05:46 Last modified:2021-11-14 00:10:07
Access level:the public Released:2002-10-18 08:05:46
Creative Commons license:CC BY
Reference information

Primary reference:
7308. A. R. Ormiston. 1967. Lower and Middle Devonian trilobites of the Canadian arctic islands. Geological Survey of Canada Bulletin 153:1-148 [M. Foote/M. Foote/M. Foote]