Taouratine Fm
Period:
Jurassic
Age Interval:
Hettangian - Oxfordian
Province:
Murzuq Basin
Type Locality and Naming
The Taouratine Formation was first described by de Lapparent and Lelubre (1948) from the Taouratine area in the eastern Illizi Basin of Algeria.
Synonym:
References:
Lithology and Thickness
In this area it can be subdivided into three units, a lower member of alternating mottled sandy claystones and ferruginous sandstones which contain plants and vertebrate remains indicative of late Jurassic age, a middle member of sandy dolomitic limestone and marls of mid-Jurassic to early Cretaceous age, and an upper unit of claystones, friable sandstones and occasional limestones which have been dated as Vraconian (late Albian-early Cenomanian). The thickness is about 350m (Hallett, 2002). The formation has been penetrated by most wells in NC 115, with a thickness of around 400m (Aziz, 2000).
Lithology Pattern:
Clayey sandstone
Relationships and Distribution
Lower contact
It unconformably overlies the Zarzaitine Fm.
Upper contact
It is unconformably overlain by the Messak Fm.
Regional extent
It is present in the Murzuq and, depending upon nomenclature?, also in the Ghadames Basins.
GeoJSON
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Fossils
In Libya, silicified plant remains and petrified logs. The plants and palynological assemblages confirm a Jurassic age, with no evidence of Cretaceous forms (LeBlanc, 2022)
Age
The overlying Messak Fm has an estimated initiation in the Kimmeridgian, and if ignore the unconformity, then the top of this formation will be in the Oxfordian. Base drawn on Fello (2001)’s Repsol regional column as base of Jurassic (used here). Jacques LeBlanc (2022) Stratigraphic Lexicon: The Sedimentary Formations of The Republic of Niger, Africa, has it spanning the entire Jurassic (see Nigerlex.geolex.org), which referenced Hallet, 2016, 2002).
Age Span:
Beginning stage:
Hettangian
Fraction up in beginning stage:
0.00
Beginning date (Ma):
201.36
Ending stage:
Oxfordian
Fraction up in the ending stage:
1.0
Ending date (Ma):
154.78
Depositional setting
Depositional pattern:
Additional Information
Compiler:
Enam O. Obiosio, Solomon Joshua Avong and Henry Nasir Suleiman (2024) - Stratigraphic Lexicon compiled from the following books:
Jacques LeBlanc (2022) Stratigraphic Lexicon: The Sedimentary Formations of The Republic of Niger, Africa. Colnes Publishing (Tallin, Estonia), 365 pp. (freely available on ResearchGate)