Geologic Time Eon

5. a once living thing that was buried and turned to stone.
6. A fossil that is useful for dating and correlating the strata in which it is found.
8. Is the age of a rock layer (or the fossils it contains) compared to other layers.
9. A fault or other body of rock cuts through another body of rock then it must be younger in age than the rock through which it cuts and displaces.
10. A major principle of stratigraphy stating that within a sequence of layers of sedimentary rock.

1. Is the time required for a quantity to reduce to half of its initial value.
2. Found in other rocks (or formations) must be older than the rock that contain them.
3. age Is the numeric age of a layer of rocks or fossils.
4. Puts geologic events in chronological order without requiring that a specific numerical age be assigned to each event.
7. Deals with assigning actual dates (in years before the present) to geological events.