Index fossils are distinct fossils used to determine the ages of rock layers due to their wide distribution and short geological range.
Index fossils are fossils of organisms that lived over a wide area and for a relatively short period of time, making them useful for determining the ages of rock layers. These fossils are easily recognizable, abundant, and have a short geologic range, aiding in precise dating of sedimentary rocks. The presence of index fossils in rock layers allows scientists to infer the approximate age of those rocks.
https://brainly.com/question/41088953