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Irhazer II Formation
The Irhazer Shale () or Irhazer II Formation is a Middle Jurassic geologic Formation (geology), formation of the Irhazer Group in the Agadez Region of Niger. Fossil ornithopod tracks have been reported from the formation.Weishampel, et al. (2004). "Dinosaur distribution." Pp. 517-607. The dinosaur ''Spinophorosaurus'' is known from the formation. Description As the overlying Tiouraren Formation of the Irhazer Group, the formation previously had been assigned an Early Cretaceous age.North of Aderbissinat at Fossilworks.orgIfayen Ignère at Fossilworks.org [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geological Formation
A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics (lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exposed in a geographical region (the stratigraphic column). It is the fundamental unit of lithostratigraphy, the study of strata or rock layers. A formation must be large enough that it can be mapped at the surface or traced in the subsurface. Formations are otherwise not defined by the thickness (geology), thickness of their rock strata, which can vary widely. They are usually, but not universally, tabular in form. They may consist of a single lithology (rock type), or of alternating beds of two or more lithologies, or even a heterogeneous mixture of lithologies, so long as this distinguishes them from adjacent bodies of rock. The concept of a geologic formation goes back to the beginnings of modern scientific geology. The term was used by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
