Tiourarén Formation
| Tiourarén Formation | |
|---|---|
| Stratigraphic range: Middle or Late Jurassic (Suggested post Bathonian, reaching either Oxfordian or even Barremian) | |
Map showing dinosaur localities around Agadez, Niger | |
| Type | Geological formation |
| Unit of | Irhazer Group |
| Underlies | Tazolé Formation (Tegama Group) |
| Overlies | Irhazer Shale |
| Thickness | ~350 m (1,150 ft) |
| Lithology | |
| Primary | Siltstone, mudstone |
| Other | Sandstone, marl, limestone |
| Location | |
| Coordinates | 16°30′N 7°48′E / 16.5°N 7.8°E |
| Approximate paleocoordinates | 8°12′N 2°30′E / 8.2°N 2.5°E |
| Region | Agadez |
| Country | Niger |
| Extent | Iullemmeden Basin |
| Type section | |
| Named for | Tiourarén hill, Agadez |
| Named by | Moody R.T.J. & Sutcliffe P.J.C. |
The Tiourarén Formation is a geological formation in the Agadez Region of Niger whose strata were originally thought to be Early Cretaceous. However, re-interpretation of the sediments showed that they are probably Middle or Late Jurassic (Bathonian-Oxfordian) in age. Other works suggested it reaches the Barremian. It is the uppermost unit of the Irhazer Group. Dinosaur remains & other vertebrates are among the fossils that have been recovered from the formation. Originally part of the "Argiles de l'Ihrazer", the Tiouaren Formation primarily comprises reddish to purple siltstones with occasional marls, limestones, and scarce channel sandstones.