Entry: Formation - showing version 3
URI: https://data.geoscience.fr/ncl/LithoStratRank/10
A body of rock identified by lithic characteristics and stratigraphic position; it is usually but not necessarily tabular and is mappable at the Earth's surface or traceable in the subsurface. Formations are the only formal lithostratigraphic units into which the stratigraphic column everywhere should be divided completely on the basis of lithology. The contrast in lithology between formations required to justify their establishment varies with the complexity of the geology of a region and the detail needed for geologic mapping and to work out its geologic history. No formation is considered justifiable and useful that cannot be delineated at the scale of geologic mapping practiced in the region. The thickness of formations may range from less than a meter to several thousand meters.
Definition
broader |
Subgroup
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category |
geology
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description |
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in scheme |
Lithostratigraphic ranks
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is described by |
litho.htm
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label |
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narrower |
Member
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nature |
Référent
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notation |
10
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pref label |
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same as |
formation
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status |
Valid
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type |
Concept
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