Igneous rocks numerical dating
By measuring the amount of the parent and daughter isotopes in a crystal, and then applying the decay rate, the actual age in years since the rock crystallized can be calculated.
An atom that has different number of neutrons but the same number of protons.
Paleomagnetic dating involves the analysis of the magnetic alignment of iron containing minerals within a rock, and is yet another useful tool for dating rocks younger than 100 million years.
The Earth’s Magnetic Poles have alternated their polarities many times in the past (changing from North – South to South – North and back).
The Geological Timescale divides the Earth’s history into several periods of differing lengths of time.
There are different ways that scientists can measure geological time.
Search for igneous rocks numerical dating:
Sedimentary and igneous rocks are often imprinted with the magnetic alignment of the Earth at the time they were formed.