guide fossil meaning in Hindi

"Phyllograptus " species are excellent index fossils or guide fossils for identifying Ordovician rocks.
Guided fossil-hunting treks allow ordinary folks to become amateur paleontologists
Index fossils ( also known as guide fossils, indicator fossils or zone fossils ) are fossils used to define and identify geologic periods ( or faunal stages ).
Fossil fans can dig it : See what you can dig up when you join this hands-on, guided fossil expedition through Old Topanga Canyon at 9 a . m . Saturday.

noun.

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
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