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The fossil remains of an organism that lived in a particular geologic age, used to identify or date the rock or rock layer in which it is found. Also called guide fossil.
(Geological Science) a fossil species that characterizes and is used to delimit a geological zone. Also called: zone fossil
a widely distributed fossil, of narrow range in time, regarded as characteristic of a given geological formation and used esp. in determining the age of related formations.
index fossil- One useful for dating and demonstrating the relation between strata in which it is found.
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|Noun||1.||index fossil - a fossil known to have lived in a particular geologic age that can be used to date the rock layer in which it is found|
fossil - the remains (or an impression) of a plant or animal that existed in a past geological age and that has been excavated from the soil