Oued Ali Formation (Middle Member) at Oued Ali: Ludlow - Pridoli, Algeria

List of taxa
Where & when
Geology
Taphonomy & methods
Metadata & references
Taxonomic list
Bivalvia - Cyrtodontida - Slavidae
Slava imperficieus
Bivalvia - Cyrtodontida - Cardiolidae
Cardiola interrupta
Bivalvia - Cardiida - Glossidae
"Isocardia" insocialis
Pterobranchia - Graptoloidea
Monograptus ultimus Perner 1899
recombined as Neocolonograptus ultimus
Pterobranchia - Graptoloidea - Monograptidae
Monograptus cf. roemeri
Monograptus colonus
Monograptus nilssoni
Monograptus fritschi
Monograptus scanicus
Monograptus sp.
Monograptus leintwardiensis
Pristiograptus sp.
Legrand 1977
Monograptus bohemicus (Barrande 1850)
recombined as Bohemograptus bohemicus
see common names

Geography
Country:Algeria
Coordinates: 29.8° North, 2.3° West (view map)
Paleocoordinates:72.2° South, 37.7° East
Basis of coordinate:based on nearby landmark
Geographic resolution:local area
Time
Period:Silurian
10 m.y. bin:Silurian 2
*Epoch:Early/Lower Ludlow - Pridoli
Key time interval:Ludlow - Pridoli
Age range of interval:427.40000 - 419.20000 m.y. ago
* legacy (obsolete) database fields
Stratigraphy
Formation:Oued Ali
Stratigraphic resolution:member
Stratigraphy comments: Middle Member, several collecting levels whose graptolite faunas collectively suggest ages between Early Ludlow and Pridoli.
Lithology and environment
Primary lithology: "shale"
Secondary lithology: "limestone"
Includes fossils?Y
Includes fossils?Y
Lithology description: Noted are graptolitic shales, gypsiferous shales, and limestone interbeds.
Environment:offshore Tectonic setting:cratonic basin
Geology comments: Formation is between the Ougarta Group sandstones below and the Zeimlet Formation sandstones above.
SEP environmental call based on scanty given information and geological context provided by source ref (PDBD 7455). Note that this unit is mud dominated but contains fairly abundant limestone beds.
Taphonomy
Collection methods and comments
Reason for describing collection:biostratigraphic analysis
Metadata
Database number:27209
Authorizer:M. Foote Enterer:M. Foote
Modifier:S. Peters Research group:marine invertebrate
Created:2002-11-22 09:57:49 Last modified:2003-05-06 14:02:54
Access level:the public Released:2002-11-22 09:57:49
Creative Commons license:CC BY
Reference information

Primary reference:

7455. W. B. N. Berry and A. J. Boucot. 1973. Correlation of the African Silurian rocks. Geological Society of America Special Paper 147:1-83 [M. Foote/M. Foote/M. Foote]

Secondary references:

7519 P. Legrand. 1977. Les Chaines d'Ougarta au Sahara algerien. In A. Martinsson (ed.), The Silurian-Devonian boundary (IUGS, Series A, Number 5) 195-202 [M. Foote/M. Foote/P. Wagner]