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Staffelegg Formation
The Staffelegg Formation (German language, German: Staffelegg-Formation, French language, French: Formation de la Staffelegg, Italian language, Italian: Formazione della Staffelegg) is a formation (geology), formation of Early Jurassic age (Hettangian, late Hettangian to Toarcian, early Toarcian stages) in the Canton of Aargau of northern Switzerland. The siltstones, marls, limestones and intermittent sandstones of the formation were deposited on the Northern Tethyan Carbonate Platform (NTCP). The Staffelegg Formation has provided fossils of the Ichthyosauria, ichthyosaur ''Eurhinosaurus, Eurhinosaurus longirostris'' and the ammonite ''Catacoeloceras, Catacoeloceras raquinianum''. Description The formation is found in the northern canton of Aargau of Switzerland and has a thickness of , and in the Mont Terri area approximately . The Staffelegg Formation is named after the Staffelegg Pass, overlies the Keuper, Keuper Group and is overlain by the Opalinus Clay. The formation compri ... [...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] |
