Here's a breakdown:
* Absolute age refers to a specific numerical value (e.g., 2.5 million years old).
* Geologic event could be a volcanic eruption, a fossil's formation, or the deposition of a sedimentary layer.
* Rock record refers to the layers of rock that contain evidence of Earth's history.
How is absolute age determined?
Absolute age is typically determined using radiometric dating, which involves analyzing the radioactive decay of isotopes within rocks or fossils.
Example:
If a geologist finds a rock containing a specific radioactive isotope with a known half-life, they can calculate how long it's been since the rock formed based on the remaining amount of that isotope.
