Here is an easy-to understand analogy for your students: relative age dating is like saying that your grandfather is older than you.
Absolute age dating is like saying you are 15 years old and your grandfather is 77 years old.
That’s because zircon is super tough – it resists weathering. Each radioactive isotope works best for particular applications.
The narrower a range of time that an animal lived, the better it is as an index of a specific time.
No bones about it, fossils are important age markers.
Pretty obvious that the dike came after the rocks it cuts through, right?
With absolute age dating, you get a real age in actual years.
Chronometric techniques include radiometric dating and radio-carbon dating, which both determine the age of materials through the decay of their radioactive elements; dendrochronology, which dates events and environmental conditions by studying tree growth rings; fluorine testing, which dates bones by calculating their fluorine content; pollen analysis, which identifies the number and type of pollen in a sample to place it in the correct historical period; and thermoluminescence, which dates ceramic materials by measuring their stored energy.
Scientists first developed absolute dating techniques at the end of the 19th century.
Before this, archaeologists and scientists relied on deductive dating methods, such as comparing rock strata formations in different regions.
Chronometric dating has advanced since the 1970s, allowing far more accurate dating of specimens.
Unlike people, you can’t really guess the age of a rock from looking at it.