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Disappointment Bay Formation
The Disappointment Bay Formation is a Formation (geology), geologic formation in Nunavut, extending from Ellesmere Island in the east to Bathurst Island (Nunavut), Bathurst Island in the west. It preserves fossils dating back to the Devonian Period (geology), period, primarily of invertebrates. Fossil Content Fish Vertebrate remains are rare in this formation. Indeterminate spine fragments are found throughout the Lowther Island off-reef limestones but are rare. A 2-centimeter wide fragment found in the 2 m-level Ammonoidea, ammonoid bed of Young Island (Nunavut), Young Island may represent a Cyathaspididae, cyathaspidid. Invertebrates Plants and algae See also * List of fossiliferous stratigraphic units in Nunavut References * Devonian Nunavut Devonian southern paleotropical deposits {{Nunavut-geo-stub ... [...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 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 Abraham Gottlob Wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
