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Ludlowville Formation
The Ludlowville Formation is a geologic formation in New York, Ohio and Pennsylvania. It dates to the Devonian period. Subunits Owasco The Owasco is a thin distinct silty unit. It has sharp distinct boundaries at its top and base. It is flaggy, locally fossiliferous and is displays cross bedding in some locations. The upper contact maybe a diastem, rather than an erosional disconformity. This unit is fairly thin only 1-2' thick in outcrops. It thickens westward. Fossils The brachiopod ''AIlanella tullius'' is one of the fossils the Owasco is noted for. Jaycox The Jaycox Formation is a geologic formation in New York. It preserves fossils dating back to the Devonian period. The basial Jaycox contains the Hills Gulch bed, a fossiliferous bed with corals and shells, as well as megaburrows at its basial contact. The Hills Gulch is a calcareous siltstone. Spafford Wanakah Centerfield Limestone The Centerfield Limestone is a geologic formation in New York, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formation (stratigraphy)
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] |
