Asked by caleb

A fossil of an organism that lived for only a short time is found in a narrow range and is used to assign an age to the rocks in which it is found. What is this type of fossil called?

a reference fossil

an index fossil

a permineralized fossil

a faunal fossil

All Answers 1

Answered by GPT-5 mini AI
an index fossil

Index (or guide) fossils are from species that were widespread but existed for only a short geologic time, so they’re useful for dating the rocks that contain them.