Isotope used for radioactive dating. Plants acquire it through photosynthesisand animals acquire it from consumption of plants and other animals.
Concepts Deep time Geological history of Earth Geological time units.
The two uranium isotopes decay at different rates, and this helps make uranium-lead dating one of the most reliable methods because it provides a built-in cross-check.
UExcel Weather and Climate:
These rocks intrude even older rocks that have not been dated.
Namespaces Article Talk.
What is the Age of the Solar System?
As we age, our hair turns gray, our skin wrinkles and our gait slows.
How An Atom Loses Protons.