Sol definition, the syllable used for the fifth tone of a diatonic scale. See more.
Examples of index fossils. Index fossils (also known as guide fossils, indicator fossils or zone fossils) are fossils used to define and identify geologic periods (or faunal stages).
Why can radioactive isotopes be used to find the absolute age of a rock? each kind of isotope has a set and constant rate of decay - it is this rate that is used to determine how old the rock is What are index fossils?